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The risk of power loss in crystalline silicon based photovoltaic modules due to micro-cracks

M.K ¨ontges a ,n ,I.Kunze a ,S.Kajari-Schr ¨oder a

,X.Breitenmoser b ,B.Bj?rneklett b

a Institute for Solar Energy Research Hamelin (ISFH),Am Ohrberg 1,D-31860Emmerthal,Germany

REC Solar AS,Kj?rboveien 29,NO-1302Sandvika,Norway

a r t i c l e i n f o

Article history:

Received 31August 2010Accepted 7October 2010

Available online 19January 2011Keywords:PV module Micro-cracks Lifetime

a b s t r a c t

Micro-cracks in wafer based silicon solar cell modules are nowadays identi?ed by a human observer with the electroluminescence (EL)method.However,the essential question of how the micro-cracks affect the PV module performance has yet to be answered.We experimentally analyze the direct impact of micro-cracks on the module power and the consequences after arti?cial aging.We show that the immediate effect of micro-cracks on the module power is small,whereas the presence of micro-cracks is potentially crucial for the performance of the module after arti?cial ageing.This con?rms the necessity to develop the means of quantifying the risk of power loss in PV modules with cracked solar cells in their lifetime,in order to enable manufacturers to discard defective modules with high risk of failure while keeping modules with uncritical micro-cracks.As a ?rst step towards risk estimation we develop an upper bound for the potential power loss of PV modules due to micro-cracks in the solar cells.This is done by simulating the impact of inactive solar cell fragments on the power of a common PV module type and PV array.We show that the largest inactive cell area of a double string protected by a bypass diode is most relevant for the power loss of the PV module.A solar cell with micro-cracks,which separate a part of less than 8%of the cell area,results in no power loss in a PV module or a PV module array for all practical cases.In between approximately 12and 50%of inactive area of a single cell in the PV module the power loss increases nearly linearly from zero to the power of one double string.

1.Introduction

Micro-cracks in solar cells are a genuine problem for photo-voltaic (PV)modules [1–3].They are hard to avoid and,up to now,basically impossible to quantify in their impact on the ef?ciency of the module during its lifetime.In particular,the presence of micro-cracks may have only a marginal effect on the power of a new module,as long as the different parts of the cell are still electrically connected.However,as the module ages and is subjected to thermal and mechanical stresses,a repeated relative movement of the cracked cell parts can result in a complete electrical separation,thus resulting in inactive cell parts.

Ideally,cells with micro-cracks are already identi?ed and rejected before they are integrated into the cell string.This is achieved within the production using,e.g.,ultrasonic methods [4],thermal ?ux thermography [5]or electroluminescence (EL)ima-ging [6].However,even if this is done perfectly,during string and module production new micro-cracks may occur.For a PV module the micro-cracks can only be detected using EL imaging.However it

is highly undesirable to reject any and every whole string or PV module with some micro-cracks,as many of these might still meet the warranted quality over the whole lifetime of the module.It is therefore imperative to develop reliable guidelines to facilitate the decision of string or module rejection due to micro-cracks.

For that purpose we choose the following approach:?rst we introduce micro-cracks into crack-free PV modules by a mechanical load test and measure the immediate in?uence of micro-cracks on the module power.We then perform an accelerated aging test on these PV modules to analyze the impact of the micro-cracks on the resulting power degradation.Finally we develop an upper bound for the power loss due to micro-cracks by simulating the electrical properties of a PV module and a PV module array with the extreme scenario of inactive cell parts.

2.Experimental analysis of the impact of micro-cracks on the PV module power

The qualitative consequences of micro-cracks in PV modules are commonly known [7].But in order to progress in the comprehen-sion of quantitative impact of micro-cracks on the module power,it is necessary to perform some systematic experimental studies.

Contents lists available at ScienceDirect

journal homepage:https://www.wendangku.net/doc/818664438.html,/locate/solmat

Solar Energy Materials &Solar Cells

doi:10.1016/j.solmat.2010.10.034

Corresponding author.

E-mail address:Marc.Koentges@ISFH.de (M.K ¨ontges).

Solar Energy Materials &Solar Cells 95(2011)1131–1137

In particular,for a good comparability of the results,it is crucial to

perform the same test sequence on several modules of the same type.

2.1.Experimental setup

To test the relevance of cell micro-cracks to the module power we use twelve 60-cell PV modules with 15.6?15.6cm 2crack-free multi-crystalline solar cells of the same type.The PV module power is measured by a cetis class AAA HALM ?asher with a reproduci-bility of 70.1%in module power for repeated measurements at standard test conditions.

An in-house developed mechanical load test equipment com-plying with the requirements of IEC 6121510.16(mechanical load test)is used as a standardized way to insert micro-cracks in the solar cells within the PV modules.The test is performed using the high pressure snow load option.The mounting during the mechan-ical load test was varied for the different modules in order to systematically introduce signi?cantly different numbers of micro-cracks into the module cells.To stress the micro-cracks caused by the mechanical load test an accelerated aging by a humidity freeze test according to IEC 6121510.12with a reduced humid time of 6h and 200cycles is performed.The sequential combination of the two tests is effective for cell crack initiation and propagation as well as subsequent electrical interruption of the metallization grid.This testing sequence represents a hostile climate with large tempera-ture ?uctuations combined with heavy snow load on the module.

For the detection of micro-cracks we use an in-house developed EL setup equipped with a ‘‘Sensicam qe’’camera from PCO using dark ?eld correction.An EL image is taken at the rated short-circuit current (I sc )of the PV module and another one at 10%of I sc .To generate the current ?ow the PV module is forward biased.The image taken at I sc is used for counting the number of cracked cells.The image taken at 10%of I sc is used to identify inactive cell areas.At this low current the voltage drop across cracks is drastically reduced.So even cell parts with a high crack resistance result in a measurable EL signal,which could not be seen at I sc .

Before and after introducing micro-cracks with a mechanical load test and after the humidity freeze test we measure the module power and take EL images.Fig.1shows the corresponding ?owchart for this test sequence.From the EL images the number of cracked cells is determined.We classify cell micro-cracks in the following way,see Fig.2:cell micro-cracks which do not generate inactive cell areas and therewith do not reduce the EL intensity in the I sc picture are classi?ed as mode A cracks.A crack is de?ned as a mode C crack if an EL image taken at 1/10of I sc reveals only background noise for the inactive cell part.Cracks seen in one or

both of the EL images resulting in cell parts with a reduced intensity but higher than the background noise are de?ned as mode B cracks.

2.2.Experimental results

The PV module power degradation due to the mechanical load test is shown in dependence of the number of micro-cracks introduced by the mechanical load in Fig.3.Here only PV modules with mode A cell cracks are included in order to assure good comparability of the results.We ?nd that cell micro-cracks cause little power loss to a PV module when they do not generate inactive cell areas (mode A).No power loss is detectible if only some cells crack in mode A.For our 60-cell PV module a power loss of about 1%is measured if half of the cells crack in mode A.From a linear regression of this data a power loss of about 2.5%can be estimated if all cells of the PV module crack in mode A.

Fig.4shows the power loss after accelerated aging by 200humidity freeze cycles as a function of the number of cracked cells.All modules show strong glass corrosion after the humidity freeze test.This corresponds to a mean degradation of approximately 3%of I sc of all PV modules.Besides this ‘‘degradation offset’’we see

that

Fig.1.Schematic of test

sequence.

Fig.2.EL images of the same solar cell with crack modes A,B and C.Left EL image is taken at I sc ;right at 10%of I sc

Fig.3.The power loss for a 60-cell PV module with 15.6?15.6cm 2sized cells due to mode A cracked cells is in the range of 0–2.5%.The module power is measured before and after introducing the cracks.Each point represents a single PV module.

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the power loss is clearly higher for modules with a higher number of cracked cells after the mechanical load test.The highest power loss found in this test is less than 10%.The electroluminescence images of the degraded PV modules show that some of the cell cracks changed from mode A to mode B,see Fig.5.In some minor cases the crack mode changed from A to C,see also Fig.5.These results highlight the importance of micro-cracks for the PV module aging.They stress the necessity of understanding the potential power losses due to micro-cracks.2.3.Discussion

The results of the experimental test sequence,of Fig.1,demon-strate the relevance of micro-cracks for the PV module aging and stress on the necessity of understanding the potential power losses due to micro-cracks.They also show the real challenge in inter-preting the relevance of micro-cracks for PV module power stability;as we have shown above,mode A cracks in the silicon wafer before arti?cial ageing only have a small impact on the PV module power,even though the power loss correlates with the

number of mode A cracked cells in the module.Nevertheless,when

arti?cial ageing is applied to PV modules with mode A cracked solar cells,the number of micro cracked cells in a module is highly relevant for the power degradation of the PV module.However,the data shown in Fig.4are substantially scattered,making a reliable quantitative prediction of the power degradation from the initial EL image quite challenging to say the least.As shown above,some mode A cracks change during arti?cial aging to mode B or even mode C cracks.Obviously,in such a case the impact of this crack on the module power will rise.However,up to now it is unknown how and when these changes occur,and with which probability this is to be expected in a given environment.

The question arises,what in?uences the power loss due to micro-cracks.Several aspects are well known,such as the cell thickness,the defect density,the texturing process,the busbar solder technology [8]and quality [2],ribbon yield strength and geometry:all these may in?uence the rate of wafer fracturing and crack propagation in the silicon wafer [9].However,for the electrical functionality of the solar cell the crack propagation through the metallization scheme is the primary parameter.Crack propagation into the metal will depend mostly on the thickness and uniformity of the Al 12.6Si 87.4eutectic of the rear metallization and the ductility and geometry of the silver front metallization.

3.Simulation of power losses due to inactive cell areas As a ?rst step towards a fundamental understanding of the connection between micro-cracks of different modes and the potential power degradation of the PV module,we numerically analyze the impact of mode C cracks,corresponding to inactive cell areas,on the module power.This represents a worst case scenario,in which any area surrounded by micro-cracks is immediately electrically isolated from the active part of the cell.As we have seen in the previous section,this is not a regular occurrence and is solely used to develop an upper bound of the potential power degradation and to analyze the in?uence of different parameters.3.1.Simulation model

In order to assess how the area of inactive cell components A inactive in?uences the PV module output,we carry out an I –V characteristic simulation of a 60-cell PV module with the free software LTSpice from

Linear Technology TM

.The model parameters used for our simulation are listed and explained in Table 1.The electrical PV module parameters are typical for today’s multi-crystalline quality PV mod-ules.Fig.6shows the circuit diagram of one solar cell.

The reverse current I R composed of the current generation,the current through the parallel resistance and the avalanche break-down current are modeled by a compact formula published by Alonso-Garcia and Ruiz [10]

I R ?j sc àV i =R p àáàá

A active

1àexp B e 1à??????????????????????????????????????ef T àV b T=ef T àV i Tp n o

e1Twhere f T is an internal barrier,V b the breakdown voltage,B e a material parameter,j sc the short current density at standard test conditions and the parallel resistance R p of a solar cell.A active is the active area of the solar cell and V i the internal voltage of the solar cell.

The direct recombination current I D1is modeled by diode D 1with a standard diode model

I D1?j 01A active exp V

i V T &'à1

e2Twhere V T is the thermal voltage at the cell

junction.

Fig.4.The power loss after a test sequence of mechanical load and 200humidity freeze cycles correlates with the number of cells cracked in the mechanical load test.Each point represents a single PV

module.

Fig.5.Example for an EL image of one cell after the mechanical load test showing almost crack mode A micro-cracks (left).The right image shows the same cell after 200cycle humidity freeze (right).Some of the micro-cracks changed to crack mode B and one small fraction changed to mode C.

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The Shockly–Read–Hall recombination current I D2is modeled by diode D 2with an ideality factor of two

I D2?j 02A active exp

V i

2V T &'à1

e3TThe voltage drop across the series resistance R S reduces the external cell voltage V to the internal voltage V i as V i ?V àR S eàI R tI D1tI D2T=A active

e4T

The series resistance R S is a lumped parameter describing the series resistance on the cell,the resistance of the interconnectors and the contact resistance between interconnector and cells.

For the electrical simulation of a cell with a fractured cell part we connect the inactive cell area A inactive in series with a break resistance R b .These two elements are in parallel to the remaining active cell area A active of that cell,see Fig.7.The sum of A inactive +A active is 243.35cm 2(A total )for each solar cell.To simulate a completely the inactive cell part is disconnected from the active cell part.For simpli?cation we introduce a graphical symbol for a broken cell,see Fig.7b.

With this model we simulate four scenarios.In scenario I we calculate the power loss of one PV module caused by a single defective cell with a variable inactive area size.Fig.8shows the circuit diagram of the whole PV module with one broken cell.The PV module consists of 60cells in series and 3bypass diodes each in parallel to 20solar cells.Below we name these 20series connected cells plus the parallel bypass diode a double string.In this scenario

the inactive area A inactive of that single solar cell is disconnected.This scenario represents the power loss introduced by a change in the cell crack from mode A to C.We also varied the breakdown voltage of that defective cell to show the importance of that parameter.

In scenario II we contact the ‘‘inactive’’cell area by the series break resistance R b to the active cell part,as shown in Fig.7.This shows the in?uence of cell cracks changing from mode A to B in a PV module.

Under realistic conditions often more than one cell of a PV module shows micro-cracks.Therefore we simulate in scenario III a module having a varying number of defective cells in a double string.The circuit diagram for scenario III is shown in Fig.9.On the one hand we simulate 19cells having the same inactive cell area and one cell with a deviant inactive cell area compared to the others.On the other hand we de?ne a number of cells having an equal size of inactive cell area in a single double string and all other cells of the module are intact.

In scenario IV we calculate the power loss of a PV module with a single defective cell in series connected with 19intact PV modules,see Fig.10.Due to isolation voltage restrictions of today’s modules

Table 1

Parameters of the PV module simulation.PV module type

Series connection with three bypass diodes Number of cells in the module/number of cells per bypass diode 60/20

Solar cell area A total

243.36cm 2

Module parameters P MPP ,I sc ,U oc ,I MPP and U MPP

228W p ,8.36A,38.1V,7.67A and 29.7V Module temperature 251C

Light intensity

1000W/m 2Inactive cell area of the defective cell variable

Parameter of IV characteristics in forward voltage for all solar cells Two diode model Saturation current J 01of ?rst diode with ideality factor one

5?10à13A/cm 2Saturation current J 02of second diode with ideality factor two 5?10à8A/cm 2Series resistance R S 1.7O cm 2

Parallel resistance R p

1?105O cm 2Short-circuit current–density j sc 34.35mA/cm 2

Parameter of IV characteristic in reverse bias for all solar cells Model of Alonso-Garcia and Ruiz [10]Dimensionless parameter B e 3

Built in junction voltage f T 0.85V Breakdown voltage V b (unless otherwise noted)

Fig.6.Equivalent circuit diagram of one solar cell.An avalanche diode is included to simulate the reverse current behavior of the solar

cell.

Fig.7.(a)Circuit diagram of a solar cell with a break resistance R b between the cell and the broken cell fraction and (b)graphical symbol for a broken

cell.

Fig.8.Circuit diagram used for scenario I and II of one solar module of 60solar cells and with three bypass diodes.One solar cell is broken in the ?rst double

string.

Fig.9.Circuit diagram used for scenario III.In one double string a various number of cells are broken.

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one would not connect much more than 20of these PV modules in series to an array.Therefore this scenario shows the upper bound for the power loss due to a single defective cell in a PV module array.3.2.Simulation results

Scenario I,in?uence of the inactive cell area and breakdown voltage:the voltage over a defective cell is in forward bias as long as the solar cell in the PV module can carry the module current I MPP .The I sc is the maximum generation current a cell can carry in forward bias and is proportional to the total cell area A total .If the total cell area is reduced so that the I sc of the cell gets below I MPP of the other cells the voltage over the defective cell becomes reverse biased.A defective cell with the inactive cell area A inactive is in forward bias if the following equation is true:A inactive A total o

I sc àI MPP

I sc

e5T

Therefore Eq.(5)gives a rough estimation to evaluate the power loss due to a defective cell in the module.The right term in Eq.(5)is 8.25%for the parameters used for the simulation shown in Table 1.So 8.25%of one single cell in the PV module may be inactive without a signi?cant module power loss.

However,with the simulation we get a more detailed picture of the power loss of a PV module.Fig.11shows the simulation of power loss as well as the current in the maximum power point (MPP).These parameters are shown as a function of the size of the inactive area of a single solar cell in the PV module for various breakdown voltages of the solar cell.Clearly the breakdown voltage has a signi?cant impact on the power loss.If the inactive cell area of the defective solar cell in the PV module violates Eq.(5),this cell is polarized in reverse bias by the other cells until the current can ?ow through the defective cell.For the simulation shown here,the inactive cell area A inactive may cover up to 8%of total wafer area without leading to any relevant power loss,which agrees well with Eq.(5).For a large 15.6?15.6cm 2solar cell 8%equals approxi-mately 20cm 2cell area.

For typical breakdown voltages of more than 15V,the bypass diode bridges the string with a defective solar cell with an inactive

cell area of at least 50%.For this type of solar cell the power loss in dependence of the inactive area is predictable without knowing the exact breakdown voltage.In this case no relevant reverse current ?ow is possible.This leads to the complete loss of the power of the double string with the defective cell.Before the bypass diode is active,the current ?ows in the reverse direction over very local areas of the defective solar cell.The current ?ow under MPP conditions of the module is shown in Fig.11.For breakdown voltages of 15V and less the current ?ows through the reverse biased defective cell and not through the bypass diode.Especially for solar cells with a breakdown voltage of less than 15V there is an increasing risk of high local current and power densities with decreasing breakdown voltage.This may lead to hot spots and thus may lead to a local damage of the lamination material [11].Furthermore with increasing inactive area the current I MPP of the defective module decreases below the nominal I MPP value of the PV module.This low I MPP current is a problem for series connected PV module in an array and is described in scenario IV.

Scenario II,in?uence of mode B cracked cells:very often cell fragments luminesce less brightly in EL images,but are not yet dark (mode B cracks).In this case the cracked cell area is still electrically connected via a fracture series resistance to the remaining cell.In our simulation we connected this cell area by a series resistance R b in parallel to the active cell area.Fig.12shows the PV module output as a function inactive area and parameter-ized by the fracture resistance R b .For 100%inactive cell area the simulation is equivalent to a PV module with an additional series resistance.In this case the module power is affected if the series resistance is in the magnitude of the source resistance of the intact PV module.For our example the source resistance in the MPP of the intact PV module is 3.9O .The simulation shows a strong in?uence on the module power if the fracture resistance R b is about 1O .A fracture resistance of approximately 10O generates nearly the same power loss as a completely inactive cell part (crack mode C).We stress that the I MPP of that module is only slightly affected as long as the fracture resistance is one order of magnitude lower than the source resistance of the module.This is important for the series connection to a module array described in scenario

IV.

Fig.10.Schematic for scenario III:PV module array of 20series connected PV

modules.Only a single solar cell in a single the PV module suffers from an inactive cell

area.

Fig.11.Simulation of the module power loss (lower part of graph)and the current in the MPP (upper part of graph)for a 60-cell PV module for various breakdown voltages V b .For one of the sixty 15.6?15.6cm 2large solar cells the inactive cell area varies from 0%(0cm 2)to 100%(243.36cm 2).

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Scenario III,in?uence of additional defective cells:we simulate the power loss of a PV module with 20defective solar cells in a double string.Fig.13shows the power loss of the module as a function of the inactive cell area of 19equal solar cells.The inactive cell area of cell number 20is used as parameter.The simulation shows that a single solar cell (cell no.20)predominantly determines the power loss of the PV module if it has a 5%larger inactive cell area compared to all the other defective cells.Therefore in most practical cases the power loss is determined by the cell with the largest inactive cell area per double string.In Fig.14the dependence of the module power on the number of cells with equal inactive cell parts in a double string shown.Even in this unlikely case the largest contribution to the power loss is already determined by the presence of one single defective cell.

Scenario IV,in?uence on PV module arrays:due to isolation voltage restrictions of today’s modules one would not connect much more than 20of these PV modules to an array.Therefore Fig.15shows the power loss of a single module depending on the inactive cell area of a single solar cell in comparison to the power loss of the same module integrated in series with 19intact modules.If the current at the MPP of a single PV module is reduced signi?cantly due to defective cells,the power loss of the single PV module does not equal the power loss in a PV module array.In a PV module array,a reduction in the current operating point would lead to a power reduction of all PV modules of the array.This is more disadvantageous in most cases than to operate the defective string at a higher current and thereby waive the power of the broken string at least partly.This effect is comprehensible by the simulated I MPP current in Fig.15.In extreme cases,the bypass diode bridges the string with the defective cell.Fig.15shows that the defective string part in the PV module array loses its power more drastically with increasing inactive cell area compared to the single module.For the PV module array again an inactive cell area of 8%is acceptable,see Fig.15.While a higher inactive cell area is more critical for the power loss of a PV module array compared to a single PV module.3.3.Discussion

The numerical simulation of the electric properties of PV modules with one or more cells with reduced active area,corre-sponding to the worst case scenario of mode C cracks,gives valuable insight into the in?uence of different parameters on the resulting power loss of the PV module considered.We showed that within one PV module the cell with the largest inactive area determines the power loss of this module.Additionally,even if several cells with exactly the same inactive area occur in one module,which is highly unlikely in realistic circumstances,the

cell

Fig.12.Simulation of the module power loss (lower graph)and the current in

maximal power point (upper graph)with the parameters of Table 1.The ‘‘inactive’’solar cell area is electrically parallel connected to the active cell part by various series break resistances.The series resistance increases in the direction of the

arrow.

Fig.13.Simulation of the power loss of a PV module with all cells defective in one double string.All cells have the same inactive cell area except for cell no.20.The inactive cell area of cell no.20is shown as parameter.While the inactive cell area of cell no.20exceeds the inactive cell area of the 19other cells the power loss is dominated by cell no.

20.

Fig.14.Simulation of the power loss of a PV module with multiple defective cells in one double string with defective cells having the same inactive cell area.

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having the greatest inactive cell area has the highest impact on the module power.This is a highly relevant observation for judging the potential risk of power loss for a given PV module:although the EL image of a module with long micro-cracks in most cells but small possible inactive areas may look disastrous,another module with only one defective cell that potentially looses a large fraction of its active area has a higher potential power loss.

Another aspect is equally crucial for the evaluation of EL images:as we have shown and explained above,a PV module can tolerate the loss of a certain percentage of the active area of a solar cell without much impact on the module power at all.In the PV module simulated here it lay at about 8%of the total cell area.Again,with this knowledge,adapted for the module type in question,the evaluation of EL images and the subsequent decision of rejection or acceptance of the module stand on a much ?rmer ground.For a module array the discussed arguments as a basis for decision hold as well.However note that the impact of a defective cell with inactive area above the threshold is much more decisive.

In reality,even under the harsh conditions of arti?cial ageing,the worst case scenario that all micro-cracks revert to mode C cracks is exceedingly unlikely.In the experiments discussed in Section 2only in a few cases a mode A crack reverted to a mode C crack,and not in a single module this occurred for all micro-cracks in the module.In contrast we found the cracked areas to be electrically connected to the active cell area to some degree.In the simulations we considered this by connecting the cracked areas with a series resistance to the active cell part.As long as this break resistance is one order of magnitude less than the module resistance in MPP conditions the power loss is low.This may be the reason why we did not ?nd a more drastic power loss after 200humidity freeze cycles in our experiment.4.Conclusion

We showed that arti?cially initiated micro-cracks in the silicon wafer do not reduce the power generation of a PV module by more than 2.5%relatively if the crack does not harm the electrical contact

between the cell fragments.However by a subsequent accelerated aging test the crack resistance between cracked cell fractions increase.Furthermore the number of cracked cells correlates with the power degradation after the accelerated aging test.

However we do not know the propagation rate for cracks in the wafer to the cell metallization under realistic conditions.This rate depends strongly on the preparation conditions of the solar cells and the PV module.To avoid power loss due to micro-cracks two strategies may be possible.The ?rst strategy is to avoid cell breakage.The second strategy may be to use a more ?exible cell metallization that prevent electrical isolation of cell parts if the silicon is broken.

For a classi?cation of cracks in the wafer,which does not harm the metallization of the cells in the initial state,we introduced a computer simulation.We assumed a worst case scenario for the calculation of the power loss due to micro-cracks by implying that the cracks isolate cell areas.We developed some reference points to assess the impact of cell micro-cracks to the power of a standard PV module with 60solar cells.Here we found that the power loss due to inactive cell area depends on the breakdown voltage of the solar cells.Only for solar cells with a breakdown voltage of equal to or more than 15V the power loss is calculable in dependence of the inactive cell area without knowing the exact breakdown charac-teristic of the cell.However for all cases cell micro-cracks of less 8%cell area do not in?uence the module power.In between approxi-mately 12and 50%of inactive cell area of a single cell in the PV module the power loss increases nearly linear from zero to the power of one double string for cells with a breakdown voltage of equal to or more than 15V.In a string protected by a bypass diode the cell with the largest inactive cell area is the most important for the power loss of the PV module.These reference points help to classify PV modules with partly cracked cells.

Acknowledgement

Funding was provided by the State of Lower Saxony.References

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modules —new concepts for a tests standard and consequences for module design with respect to bypass diodes,in:Proceedings of the 26th PVSC,IEEE,Anaheim,Canada 1997,pp.

1129–1132.

Fig.15.Simulation of the power loss of a single PV module with a single solar cell

having a varying inactive cell area.The simulated power loss of a 20s PV module array containing this defective module is also shown.More than 8%of inactive cell area in the 20s module array leads to a much higher power loss compared to the stand alone PV module.

M.K¨o ntges et al./Solar Energy Materials &Solar Cells 95(2011)1131–11371137

The way常见用法

The way 的用法 Ⅰ常见用法： 1)the way+ that 2)the way + in which（最为正式的用法） 3)the way + 省略（最为自然的用法）举例：I like the way in which he talks. I like the way that he talks. I like the way he talks. Ⅱ习惯用法：在当代美国英语中，the way用作为副词的对格，“the way+ 从句”实际上相当于一个状语从句来修饰整个句子。 1)The way =as I am talking to you just the way I’d talk to my own child. He did not do it the way his friends did. Most fruits are naturally sweet and we can eat them just the way they are—all we have to do is to clean and peel them. 2）The way= according to the way/ judging from the way The way you answer the question, you are an excellent student. The way most people look at you, you’d think trash man is a monster. 3）The way =how/ how much No one can imagine the way he missed her. 4）The way =because

The way的用法及其含义(二)

The way的用法及其含义（二）二、the way在句中的语法作用 the way在句中可以作主语、宾语或表语： 1.作主语 The way you are doing it is completely crazy.你这个干法简直发疯。 The way she puts on that accent really irritates me. 她故意操那种口音的样子实在令我恼火。The way she behaved towards him was utterly ruthless. 她对待他真是无情至极。 Words are important, but the way a person stands, folds his or her arms or moves his or her hands can also give us information about his or her feelings. 言语固然重要,但人的站姿,抱臂的方式和手势也回告诉我们他(她)的情感。 2.作宾语 I hate the way she stared at me.我讨厌她盯我看的样子。 We like the way that her hair hangs down.我们喜欢她的头发笔直地垂下来。 You could tell she was foreign by the way she was dressed. 从她的穿著就可以看出她是外国人。 She could not hide her amusement at the way he was dancing. 她见他跳舞的姿势，忍俊不禁。 3.作表语 This is the way the accident happened.这就是事故如何发生的。 Believe it or not, that's the way it is. 信不信由你, 反正事情就是这样。 That's the way I look at it, too. 我也是这么想。 That was the way minority nationalities were treated in old China. 那就是少数民族在旧中

(完整版)the的用法

定冠词the的用法：定冠词the与指示代词this ,that同源,有“那(这)个”的意思,但较弱,可以和一个名词连用,来表示某个或某些特定的人或东西. (1)特指双方都明白的人或物 Take the medicine.把药吃了. (2)上文提到过的人或事 He bought a house.他买了幢房子. I've been to the house.我去过那幢房子. (3)指世界上独一无二的事物 the sun ,the sky ,the moon, the earth (4)单数名词连用表示一类事物 the dollar 美元 the fox 狐狸或与形容词或分词连用,表示一类人 the rich 富人 the living 生者 (5)用在序数词和形容词最高级,及形容词等前面 Where do you live?你住在哪? I live on the second floor.我住在二楼. That's the very thing I've been looking for.那正是我要找的东西. (6)与复数名词连用,指整个群体 They are the teachers of this school.(指全体教师) They are teachers of this school.(指部分教师) (7)表示所有,相当于物主代词,用在表示身体部位的名词前 She caught me by the arm.她抓住了我的手臂. (8)用在某些有普通名词构成的国家名称,机关团体,阶级等专有名词前 the People's Republic of China 中华人民共和国 the United States 美国 (9)用在表示乐器的名词前 She plays the piano.她会弹钢琴. (10)用在姓氏的复数名词之前,表示一家人 the Greens 格林一家人(或格林夫妇) (11)用在惯用语中 in the day, in the morning... the day before yesterday, the next morning... in the sky... in the dark... in the end... on the whole, by the way...

“the way+从句”结构的意义及用法

“tｈｅwａｙ+从句”结构的意义及用法首先让我们来看下面这个句子: Ｒead the foｌloｗｉnｇpassagｅａnd talkａbout ｉt wi ｔh your classmaｔes．Try tｏｔeｌl whaｔyｏu thiｎk ｏf Tom aｎd ｏｆｔhe ｗay the chiｌｄrenｔrｅated ｈim. 在这个句子中，ｔhe waｙ是先行词,后面是省略了关系副词that或in whｉch的定语从句。下面我们将叙述“the ｗaｙ+从句”结构的用法。 1.tｈe wａy之后，引导定语从句的关系词是tｈat而不是hoｗ,因此，<<现代英语惯用法词典＞＞中所给出的下面两个句子是错误的：Ｔhｉs is ｔｈeｗayｈowｉtｈａppened. This is the way how he ａlwａｙs treats me. 2．在正式语体中,thaｔ可被in which所代替;在非正式语体中，ｔhat则往往省略。由此我们得到theｗay后接定语从句时的三种模式：1) tｈe ｗaｙ＋ｔhａt-从句２）the way +ｉn whiｃh－从句3) the ｗay +从句例如：Ｔｈe way(in whiｃh ，thａt) ｔhｅｓｅｃomｒade ｓloｏｋａｔｐrobｌems is wrong．这些同志看问题的方法

不对。Ｔｈｅｗａy(that ,ｉn ｗhiｃh)yoｕ’ｒe doinｇit is comple ｔeｌy crａzy.你这么个干法,简直发疯。 Wｅａdmiｒｅd him for thｅｗay ｉｎｗhｉch he fａｃeｓdiｆficultieｓ． Waｌlａｃe ａｎd Ｄarwiｎｇreed ｏn the way ｉｎwhi ｃh ｄｉfｆｅrｅnt forms ｏf life had ｂegｕn.华莱士和达尔文对不同类型的生物是如何起源的持相同的观点。 Thｉs is ｔｈe ｗaｙ（tｈａｔ) hｅdｉd it. I lｉkeｄｔhe waｙ(ｔhat) ｓｈeｏｒganized ｔhe ｍeetｉng． 3.theｗay(tｈat)有时可以与hｏw(作“如何”解）通用。例如： That’s tｈe ｗaｙ(tｈaｔ) shｅspoke. = Tｈat’s how shｅspoke.

way 用法

表示“方式”、“方法”，注意以下用法： 1.表示用某种方法或按某种方式，通常用介词in(此介词有时可省略)。如： Do it (in) your own way. 按你自己的方法做吧。 Please do not talk (in) that way. 请不要那样说。 2.表示做某事的方式或方法，其后可接不定式或of doing sth。如： It’s the best way of studying [to study] English. 这是学习英语的最好方法。 There are different ways to do [of doing] it. 做这事有不同的办法。 3.其后通常可直接跟一个定语从句(不用任何引导词)，也可跟由that 或in which 引导的定语从句，但是其后的从句不能由how 来引导。如：我不喜欢他说话的态度。正：I don’t like the way he spoke. 正：I don’t like the way that he spoke. 正：I don’t like the way in which he spoke. 误：I don’t like the way how he spoke. 4.注意以下各句the way 的用法： That’s the way (=how) he spoke. 那就是他说话的方式。 Nobody else loves you the way(=as) I do. 没有人像我这样爱你。 The way (=According as) you are studying now, you won’tmake much progress. 根据你现在学习情况来看，你不会有多大的进步。 2007年陕西省高考英语中有这样一道单项填空题： ——I think he is taking an active part insocial work. ——I agree with you_____. A、in a way B、on the way C、by the way D、in the way 此题答案选A。要想弄清为什么选A，而不选其他几项，则要弄清选项中含way的四个短语的不同意义和用法，下面我们就对此作一归纳和小结。一、in a way的用法表示：在一定程度上，从某方面说。如： In a way he was right.在某种程度上他是对的。注：in a way也可说成in one way。二、on the way的用法 1、表示：即将来(去)，就要来(去)。如： Spring is on the way.春天快到了。 I'd better be on my way soon.我最好还是快点儿走。 Radio forecasts said a sixth-grade wind was on the way.无线电预报说将有六级大风。 2、表示：在路上，在行进中。如： He stopped for breakfast on the way.他中途停下吃早点。 We had some good laughs on the way.我们在路上好好笑了一阵子。 3、表示：(婴儿)尚未出生。如： She has two children with another one on the way.她有两个孩子，现在还怀着一个。 She's got five children，and another one is on the way.她已经有5个孩子了，另一个又快生了。三、by the way的用法

The way的用法及其含义(一)

The way的用法及其含义（一）有这样一个句子：In 1770 the room was completed the way she wanted. 1770年，这间琥珀屋按照她的要求完成了。 the way在句中的语法作用是什么？其意义如何？在阅读时，学生经常会碰到一些含有the way 的句子，如：No one knows the way he invented the machine. He did not do the experiment the way his teacher told him.等等。他们对the way 的用法和含义比较模糊。在这几个句子中，the way之后的部分都是定语从句。第一句的意思是，“没人知道他是怎样发明这台机器的。”the way的意思相当于how；第二句的意思是，“他没有按照老师说的那样做实验。”the way 的意思相当于as。在In 1770 the room was completed the way she wanted.这句话中，the way也是as的含义。随着现代英语的发展，the way的用法已越来越普遍了。下面，我们从the way的语法作用和意义等方面做一考查和分析：一、the way作先行词，后接定语从句以下3种表达都是正确的。例如：“我喜欢她笑的样子。” 1. the way+ in which +从句 I like the way in which she smiles. 2. the way+ that +从句 I like the way that she smiles. 3. the way + 从句(省略了in which或that) I like the way she smiles. 又如：“火灾如何发生的，有好几种说法。” 1. There were several theories about the way in which the fire started. 2. There were several theories about the way that the fire started.

way 的用法

way 的用法【语境展示】 1. Now I’ll show you how to do the experiment in a different way. 下面我来演示如何用一种不同的方法做这个实验。 2. The teacher had a strange way to make his classes lively and interesting. 这位老师有种奇怪的办法让他的课生动有趣。 3. Can you tell me the best way of working out this problem? 你能告诉我算出这道题的最好方法吗？ 4. I don’t know the way (that / in which) he helped her out. 我不知道他用什么方法帮助她摆脱困境的。 5. The way (that / which) he talked about to solve the problem was difficult to understand. 他所谈到的解决这个问题的方法难以理解。 6. I don’t like the way that / which is being widely used for saving water. 我不喜欢这种正在被广泛使用的节水方法。 7. They did not do it the way we do now. 他们以前的做法和我们现在不一样。【归纳总结】 ●way作“方法，方式”讲时，如表示“以……方式”，前面常加介词in。如例1； ●way作“方法，方式”讲时，其后可接不定式to do sth.，也可接of doing sth. 作定语，表示做某事的方法。如例2，例3；

the-way-的用法讲解学习

t h e-w a y-的用法

The way 的用法 "the way+从句"结构在英语教科书中出现的频率较高, the way 是先行词, 其后是定语从句.它有三种表达形式:1) the way+that 2)the way+ in which 3)the way + 从句(省略了that或in which),在通常情况下, 用in which 引导的定语从句最为正式,用that的次之,而省略了关系代词that 或 in which 的, 反而显得更自然,最为常用.如下面三句话所示,其意义相同. I like the way in which he talks. I like the way that he talks. I like the way he talks. 一.在当代美国英语中,the way用作为副词的对格,"the way+从句"实际上相当于一个状语从句来修饰全句. the way=as 1)I'm talking to you just the way I'd talk to a boy of my own. 我和你说话就象和自己孩子说话一样. 2)He did not do it the way his friend did. 他没有象他朋友那样去做此事. 3)Most fruits are naturally sweet and we can eat them just the way they are ----all we have to do is clean or peel them . 大部分水果天然甜润,可以直接食用,我们只需要把他们清洗一下或去皮.

way的用法总结大全

way的用法总结大全 way的用法你知道多少，今天给大家带来way的用法，希望能够帮助到大家，下面就和大家分享，来欣赏一下吧。 way的用法总结大全 way的意思 n. 道路,方法,方向,某方面 adv. 远远地，大大地 way用法 way可以用作名词 way的基本意思是“路,道,街,径”,一般用来指具体的“路,道路”,也可指通向某地的“方向”“路线”或做某事所采用的手段,即“方式,方法”。way还可指“习俗,作风”“距离”“附近,周围”“某方面”等。 way作“方法,方式,手段”解时,前面常加介词in。如果way前有this, that等限定词,介词可省略,但如果放在句首,介词则不可省略。

way作“方式,方法”解时,其后可接of v -ing或to- v 作定语,也可接定语从句,引导从句的关系代词或关系副词常可省略。 way用作名词的用法例句 I am on my way to the grocery store.我正在去杂货店的路上。 We lost the way in the dark.我们在黑夜中迷路了。 He asked me the way to London.他问我去伦敦的路。 way可以用作副词 way用作副词时意思是“远远地,大大地”,通常指在程度或距离上有一定的差距。 way back表示“很久以前”。 way用作副词的用法例句 It seems like Im always way too busy with work.我工作总是太忙了。 His ideas were way ahead of his time.他的思想远远超越了他那个时代。 She finished the race way ahead of the other runners.她第一个跑到终点,远远领先于其他选手。 way用法例句

the_way的用法大全教案资料

t h e_w a y的用法大全

The way 在the way+从句中, the way 是先行词, 其后是定语从句.它有三种表达形式:1) the way+that 2)the way+ in which 3)the way + 从句(省略了that或in which),在通常情况下, 用in which 引导的定语从句最为正式,用that的次之,而省略了关系代词that 或 in which 的, 反而显得更自然,最为常用.如下面三句话所示,其意义相同. I like the way in which he talks. I like the way that he talks. I like the way he talks. 如果怕弄混淆，下面的可以不看了另外，在当代美国英语中,the way用作为副词的对格,"the way+从句"实际上相当于一个状语从句来修饰全句. the way=as 1)I'm talking to you just the way I'd talk to a boy of my own. 我和你说话就象和自己孩子说话一样. 2)He did not do it the way his friend did. 他没有象他朋友那样去做此事. 3)Most fruits are naturally sweet and we can eat them just the way they are ----all we have to do is clean or peel them . 大部分水果天然甜润,可以直接食用,我们只需要把他们清洗一下或去皮. the way=according to the way/judging from the way 4)The way you answer the qquestions, you must be an excellent student. 从你回答就知道,你是一个优秀的学生. 5)The way most people look at you, you'd think a trashman was a monster. 从大多数人看你的目光中,你就知道垃圾工在他们眼里是怪物. the way=how/how much 6)I know where you are from by the way you pronounce my name. 从你叫我名字的音调中,我知道你哪里人. 7)No one can imaine the way he misses her. 人们很想想象他是多么想念她. the way=because 8) No wonder that girls looks down upon me, the way you encourage her. 难怪那姑娘看不起我, 原来是你怂恿的

the way 的用法

The way 的用法 "the way+从句"结构在英语教科书中出现的频率较高, the way 是先行词, 其后是定语从句.它有三种表达形式:1) the way+that 2)the way+ in which 3)the way + 从句(省略了that或in which),在通常情况下, 用in which 引导的定语从句最为正式,用that的次之,而省略了关系代词that 或in which 的, 反而显得更自然,最为常用.如下面三句话所示,其意义相同. I like the way in which he talks. I like the way that he talks. I like the way he talks. 一.在当代美国英语中,the way用作为副词的对格,"the way+从句"实际上相当于一个状语从句来修饰全句. the way=as 1)I'm talking to you just the way I'd talk to a boy of my own. 我和你说话就象和自己孩子说话一样. 2)He did not do it the way his friend did. 他没有象他朋友那样去做此事. 3)Most fruits are naturally sweet and we can eat them just the way they are ----all we have to do is clean or peel them . 大部分水果天然甜润,可以直接食用,我们只需要把他们清洗一下或去皮.

the way=according to the way/judging from the way 4)The way you answer the qquestions, you must be an excellent student. 从你回答就知道,你是一个优秀的学生. 5)The way most people look at you, you'd think a trashman was a monster. 从大多数人看你的目光中,你就知道垃圾工在他们眼里是怪物. the way=how/how much 6)I know where you are from by the way you pronounce my name. 从你叫我名字的音调中,我知道你哪里人. 7)No one can imaine the way he misses her. 人们很想想象他是多么想念她. the way=because 8) No wonder that girls looks down upon me, the way you encourage her. 难怪那姑娘看不起我, 原来是你怂恿的 the way =while/when(表示对比) 9)From that day on, they walked into the classroom carrying defeat on their shoulders the way other students carried textbooks under their arms. 从那天起,其他同学是夹着书本来上课,而他们却带着"失败"的思想负担来上课.

The way的用法及其含义(三)

The way的用法及其含义（三）三、the way的语义 1. the way=as（像） Please do it the way I’ve told you.请按照我告诉你的那样做。 I'm talking to you just the way I'd talk to a boy of my own.我和你说话就像和自己孩子说话一样。 Plant need water the way they need sun light. 植物需要水就像它们需要阳光一样。 2. the way=how（怎样，多么） No one can imagine the way he misses her.没人能够想象出他是多么想念她！ I want to find out the way a volcano has formed.我想弄清楚火山是怎样形成的。 He was filled with anger at the way he had been treated.他因遭受如此待遇而怒火满腔。That’s the way she speaks.她就是那样讲话的。 3. the way=according as （根据） The way you answer the questions, you must be an excellent student.从你回答问题来看，你一定是名优秀的学生。 The way most people look at you, you'd think a trash man was a monster.从大多数人看你的目光中,你就知道垃圾工在他们眼里是怪物。 The way I look at it, it’s not what you do that matters so much.依我看，重要的并不是你做什么。 I might have been his son the way he talked.根据他说话的样子，好像我是他的儿子一样。One would think these men owned the earth the way they behave.他们这样行动，人家竟会以为他们是地球的主人。

way的用法

一．Way：“方式”、“方法” 1.表示用某种方法或按某种方式 Do it (in) your own way. Please do not talk (in) that way. 2.表示做某事的方式或方法 It’s the best way of studying [to study] English.。 There are different ways to do [of doing] it. 3.其后通常可直接跟一个定语从句(不用任何引导词)，也可跟由that 或in which 引导的定语从句正：I don’t like the way he spoke. I don’t like the way that he spoke. I don’t like the way in which he spoke.误：I don’t like the way how he spoke. 4. the way 的从句 That’s the way (=how) he spoke. I know where you are from by the way you pronounce my name. That was the way minority nationalities were treated in old China. Nobody else loves you the way(=as) I do. He did not do it the way his friend did. 二．固定搭配 1. In a/one way：In a way he was right. 2. In the way /get in one’s way I'm afraid your car is in the way， If you are not going to help，at least don't get in the way. You'll have to move－you're in my way. 3. in no way Theory can in no way be separated from practice. 4. On the way (to……) Let’s wait a few moments. He is on the way Spring is on the way. Radio forecasts said a sixth-grade wind was on the way. She has two children with another one on the way. 5. By the way By the way，do you know where Mary lives? 6. By way of Learn English by way of watching US TV series. 8. under way 1. Elbow one’s way He elbowed his way to the front of the queue. 2. shoulder one’s way 3. feel one‘s way 摸索着向前走；We couldn’t see anything in the cave, so we had to feel our way out 4. fight/force one’s way 突破。。。而前进The surrounded soldiers fought their way out. 5.. push/thrust one‘s way（在人群中）挤出一条路He pushed his way through the crowd. 6. wind one’s way 蜿蜒前进 7. lead the way 带路，领路；示范 8. lose one‘s way 迷失方向 9. clear the way 排除障碍，开路迷路 10. make one’s way 前进，行进The team slowly made their way through the jungle.

the way的用法大全

在the way+从句中, the way 是先行词, 其后是定语从句.它有三种表达形式:1) the way+that 2)the way+ in which 3)the way + 从句(省略了that或in which),在通常情况下, 用in which 引导的定语从句最为正式,用that的次之,而省略了关系代词that 或in which 的, 反而显得更自然,最为常用.如下面三句话所示,其意义相同. I like the way in which he talks. I like the way that he talks. I like the way he talks. 如果怕弄混淆，下面的可以不看了另外，在当代美国英语中,the way用作为副词的对格,"the way+从句"实际上相当于一个状语从句来修饰全句. the way=as 1)I'm talking to you just the way I'd talk to a boy of my own. 我和你说话就象和自己孩子说话一样. 2)He did not do it the way his friend did. 他没有象他朋友那样去做此事. 3)Most fruits are naturally sweet and we can eat them just the way they are ----all we have to do is clean or peel them . 大部分水果天然甜润,可以直接食用,我们只需要把他们清洗一下或去皮. the way=according to the way/judging from the way 4)The way you answer the qquestions, you must be an excellent student. 从你回答就知道,你是一个优秀的学生. 5)The way most people look at you, you'd think a trashman was a monster. 从大多数人看你的目光中,你就知道垃圾工在他们眼里是怪物. the way=how/how much 6)I know where you are from by the way you pronounce my name. 从你叫我名字的音调中,我知道你哪里人. 7)No one can imaine the way he misses her. 人们很想想象他是多么想念她. the way=because 8) No wonder that girls looks down upon me, the way you encourage her. 难怪那姑娘看不起我, 原来是你怂恿的 the way =while/when(表示对比) 9)From that day on, they walked into the classroom carrying defeat on their shoulders the way other students carried textbooks under their arms.

“the-way+从句”结构的意义及用法知识讲解

“the way+从句”结构的意义及用法首先让我们来看下面这个句子： Read the following passage and talk about it with your classmates. Try to tell what you think of Tom and of the way the children treated him. 在这个句子中，the way是先行词，后面是省略了关系副词that 或in which的定语从句。下面我们将叙述“the way+从句”结构的用法。 1．the way之后，引导定语从句的关系词是that而不是how,因此，<<现代英语惯用法词典>>中所给出的下面两个句子是错误的：This is the way how it happened. This is the way how he always treats me. 2. 在正式语体中，that可被in which所代替；在非正式语体中，that则往往省略。由此我们得到the way后接定语从句时的三种模式：1) the way +that-从句2) the way +in which-从句3) the way +从句例如：The way(in which ,that) these comrades look at problems is wrong.这些同志看问题的方法不对。

The way(that ,in which)you’re doing it is completely crazy.你这么个干法，简直发疯。 We admired him for the way in which he faces difficulties. Wallace and Darwin greed on the way in which different forms of life had begun.华莱士和达尔文对不同类型的生物是如何起源的持相同的观点。 This is the way (that) he did it. I liked the way (that) she organized the meeting. 3.the way(that)有时可以与how(作“如何”解)通用。例如： That’s the way (that) she spoke. = That’s how she spoke. I should like to know the way/how you learned to master the fundamental technique within so short a time. 4．the way的其它用法：以上我们讲的都是用作先行词的the way，下面我们将叙述它的一些用法。

定冠词the的12种用法

定冠词the的12种用法定冠词the 的12 种用法，全知道?快来一起学习吧。下面就和大家分享，来欣赏一下吧。定冠词the 的12 种用法，全知道? 定冠词the用在各种名词前面，目的是对这个名词做个记号，表示它的特指属性。所以在词汇表中，定冠词the 的词义是“这个，那个，这些，那些”，可见，the 即可以放在可数名词前，也可以修饰不可数名词，the 后面的名词可以是单数，也可以是复数。定冠词的基本用法： (1) 表示对某人、某物进行特指，所谓的特指就是“不是别的，就是那个!”如： The girl with a red cap is Susan. 戴了个红帽子的女孩是苏珊。 (2) 一旦用到the，表示谈话的俩人都知道说的谁、说的啥。如：

The dog is sick. 狗狗病了。(双方都知道是哪一只狗) (3) 前面提到过的，后文又提到。如： There is a cat in the tree.Thecat is black. 树上有一只猫，猫是黑色的。 (4) 表示世界上唯一的事物。如： The Great Wall is a wonder.万里长城是个奇迹。(5) 方位名词前。如： thenorth of the Yangtze River 长江以北地区 (6) 在序数词和形容词最高级的前面。如： Who is the first?谁第一个? Sam is the tallest.山姆最高。但是不能认为，最高级前必须加the，如： My best friend. 我最好的朋友。 (7) 在乐器前。如： play the flute 吹笛子

Way的用法

Way用法 A:I think you should phone Jenny and say sorry to her. B:_______. It was her fault. A. No way B. Not possible C. No chance D. Not at all 说明：正确答案是A. No way，意思是“别想！没门！决不！” 我认为你应该打电话给珍妮并向她道歉。没门！这是她的错。再看两个关于no way的例句：（1）Give up our tea break? NO way! 让我们放弃喝茶的休息时间？没门儿！（2）No way will I go on working for that boss. 我决不再给那个老板干了。 way一词含义丰富，由它构成的短语用法也很灵活。为了便于同学们掌握和用好它，现结合实例将其用法归纳如下：一、way的含义 1. 路线

He asked me the way to London. 他问我去伦敦的路。 We had to pick our way along the muddy track. 我们不得不在泥泞的小道上择路而行。 2. （沿某）方向 Look this way, please. 请往这边看。 Kindly step this way, ladies and gentlemen. 女士们、先生们，请这边走。 Look both ways before crossing the road. 过马路前向两边看一看。 Make sure that the sign is right way up. 一定要把符号的上下弄对。 3. 道、路、街，常用以构成复合词 a highway（公路），a waterway（水路），a railway（铁路），wayside（路边）

way与time的特殊用法

way/time的特殊用法 1、当先行词是way意思为”方式.方法”的时候,引导定语从句的关系词有下列3种形式： Way在从句中做宾语 The way that / which he explained to us is quite simple. Way在从句中做状语 The way t hat /in which he explained the sentence to us is quite simple. 2、当先行词是time时,若time表示次数时,应用关系代词that引导定语从句,that可以省略; 若time表示”一段时间”讲时,应用关系副词when或介词at/during + which引导定语从句 1.Is this factory _______ we visited last year? 2.Is this the factory-------we visited last year? A. where B in which C the one D which 3. This is the last time _________ I shall give you a lesson. A. when B that C which D in which 4.I don’t like the way ________ you laugh at her. A . that B on which C which D as 5.He didn’t understand the wa y ________ I worked out the problem. A which B in which C where D what 6.I could hardly remember how many times----I’ve failed. A that B which C in which D when 7.This is the second time--------the president has visited the country. A which B where C that D in which 8.This was at a time------there were no televisions, no computers or radios. A what B when C which D that