Brian Carlisle Adept Technology A Pivoting Gripper for Feeding Industrial Parts

A Pivoting Gripper for Feeding Industrial Parts

Brian Carlisle Adept Technology Ken Goldberg

USC

Anil Rao

Univ.Utrecht

Jeff Wiegley

USC

To be cost effective and highly precise,many industrial as-sembly robots have only four degrees of freedom(D.O.F.) plus a binary pneumatic gripper.Such robots commonly permit parts to be rotated only about a vertical axis.How-ever it is often necessary to reorient parts about other axes prior to assembly.In this paper we describe a way to ori-ent parts about an arbitrary axis by introducing a rotating bearing between the jaws of a simple gripper.

Based on this mechanism,we are developing a rapidly con?gurable vision-based system for feeding parts.In this system,a camera determines initialpart pose;the robot then reorients the part to achieve a desired?nal pose.We have implemented a prototype version in our laboratory using a commercially-available robot system.

1Introduction

To automate the assembly of mechanical components,parts must precisely oriented prior to packing or insertion.A parts feeder is a machine that orients parts.Currently,the design of parts feeders is a black art that is responsible for up to30%of the cost and50%of workcell failures [21,3,5,30,31].“The real problem is not part transfer but part orientation.”,Frank Riley,Bodine Corporation[27, p.316,his italics].Thus there is a demand for a parts feeder that can be reprogrammed rather than physically modi?ed when part geometry changes.

Our feeder design combines machine vision with a high-speed robot arm.The system is programmed based on the type of part to be fed.During operation,a collection of like parts are randomly scattered on a?at worktable where they are subject to the force of gravity.An overhead vision system determines the pose(position and orientation)of Adept Technology,Inc.,150Rose Orchard Way,San Jose,CA 95134.(408)432-0888.

Institute for Robotics and Intelligent Systems,Computer Sci-ence Department,University of Southern California,Los Angeles, CA90089-0273,(213)740-9080,goldberg@https://www.wendangku.net/doc/b817757931.html,.Gold-berg and Wiegley are supported by the National Science Founda-tion under Award No.IRI-9123747,and by an equipment grant from Adept Technology Inc.

Department of Computer Science,Utrecht University,P.O. Box80.089,Padualaan14,3508TB Utrecht,The Netherlands. Rao is supported by the ESPRIT Basic Research Action No.6546 (project PRoMotion).

Institute for Robotics and Intelligent Systems,Computer Sci-ence Department,University of Southern

California.Figure1:A parts feeder using a commercially-available system that integrates machine vision,high-speed robot arm, and pivoting gripper.This illustration shows the system feeding rectangular parts into a square pallet.

each part.The robot arm then picks up each part and moves it into a desired?nal pose as illustrated in Figure1.

To be cost effective,fast,and highly precise,commercial assembly robots usually have only four degrees of freedom (4D.O.F.).However parts must be reoriented and reposi-tioned through six degrees of freedom(6D.O.F.).To close this gap,we have designed a gripper with a rotational pivot between its jaws to provide an extra degree of freedom. Since cost and weight are critical,we note that the pivoting axis need not be actuated:it is possible to pick up each part along an axis offset from its center of mass and use on the force of gravity to rotate the part as illustrated in Figure2. In this paper we describe related work on parts feeders and robot gripper mechanisms.In Sections3and4we describe the pivoting mechanism in detail and our experiments with a vision-based parts feeding https://www.wendangku.net/doc/b817757931.html,st,we discuss the advantages and disadvantages of the proposed system and describes avenues for future research.

Figure 2:The ?gure shows 4snapshots progressing from left to right.The gripper grasps the rectangular part along an axis offset from its center of mass,lifts it off the table,and uses the force of gravity to rotate the part into a standing orientation.

2Related Work

To feed parts,manufacturers generally rely on passive de-vices that use mechanical ?lters to reject all parts except those in a desired orientation.Rejected parts are recycled for another pass through the ?lter.The most common type of feeder is the vibratory bowl feeder ,where parts in a bowl are vibrated with a rotary motion so that they climb a helical track.As they climb,a sequence of baf?es and cutouts in the track creates a mechanical “?lter”that causes parts in all but one orientation to fall back into the bowl for another attempt at running the gauntlet [3,27,29].To improve feedrate,it is sometimes possible to design the track so as to mechan-ically rotate parts into a desired orientation (this is known as conversion ).Related methods use centrifugal forces [5],reciprocating forks,or belts to move parts through the ?lter [26].The biggest disadvantage with such methods is that when part geometry changes,the ?lters must be mechani-cally redesigned with a manual trial-and-error process.There are currently no systematic methods for designing ?lters;it is a “black art”performed by specialists through trial and error.Filters must be tested and incrementally modi?ed when they cause parts to jam.The dif?culty is that a tweak that avoids parts jamming in one orientation may cause parts to jam in another [8,39].

Sony’s APOS parts feeder [12]uses an array of nests (silhouette traps)cut into a vibrating plate.The nests and the vibratory motion are designed so that the part will remain in the nest only in a particular orientation.By tilting the plate and letting parts ?ow across it,the nests eventually ?ll up with parts in the desired orientation.Although the vibratory motion is under software control,specialized mechanical nests must be designed for each part and jamming must be avoided as with bowl feeders [19].Singer and Seering [32]proposed several designs for programmable parts feeders where programmed vibration was used to drive parts into a stable orientation.These methods can be useful for bringing parts into one of several “low-energy”poses where its center of mass is as low as possible.

In the early 1980’s,several researchers used sensors to determine the pose of parts delivered by a vibratory track [26].Sensors such as tactile probes [9,36],photocells [10],?beroptic sensors [23],and machine vision systems [11,33]were employed.Once part pose was determined,air-jets and

trapdoors were used to group parts in similar poses.Adept Technology Inc.has several commercial installations that use a 4DOF robot to reorient parts in the plane.We know of no system that combines vision with a 4DOF robot to rapidly orient parts in 6DOF.

Developing a task-based robot motion planner has been a goal in robotics since the early days [22,34,16].Paul’s HAND EYE system for solving the “instant insanity”prob-lem was the ?rst to automatically generate intermediate part poses when a transformation could not be accomplished in a single motion due to limits on reachability or arm kinemat-ics.Since then,a variety of algorithms have been developed for robot motion planning [15].In particular Tournassoud,Lozano-Perez,and Mazer [35]considered the problem of moving polyhedral parts from one pose to another using a sequence of regrasping actions with a 6DOF robot and parallel-jaw gripper.The authors took advantage of the fact that parts generally have a ?nite number of stable poses.We note that both HAND EYE and HANDEY used a 6DOF arm to reorient parts by regrasping.Quoting from [35]:

Part motions during which the object remains in contact with the hand...can only be performed by a dextrous hand as they rely on precise control of forces exerted on the object.

The authors suggest how a dextrous hand might reorient a pen by grasping it below the center of mass and relaxing the grasp force so that it rotates into a new orientation.In this paper we show that such manipulation can be achieved with-out precise force control using a mechanical modi?cation to the parallel-jaw gripper.

The text by Kato and Sadamoto [13]includes detailed photos and drawings of over 150novel mechanisms for robot end effectors.Perhaps the closest ancestor of our pivoting design is the mechanism developed by John Birk at the University of Rhode Island,which was also motivated by the need to orient parts.Birk’s hand [1]has a powered belt that causes parts to rotate about an axis parallel to the gripper jaws rather than about an axis perpendicular to the jaws as in our design.A similar pivoting joint is standard on most C-clamps available in hardware stores.We note that such clamps only have a pivot on one jaw so that the pivot is immobilized once the part is grasped.

Figure3:An exploded view of the mechanism for one pivoting pad.Frictional resistance to torsional and axial forces are reduced with needle and thrust bearings as illustrated.The contacting pad can be of?at hard rubber(in our case a pencil eraser).The pad turns with the part,thereby insuring frictional resistance to slip as the part is lifted and transported.

Goldberg and Furst developed a parallel-jaw gripper with a translational bearing rather than a rotational bearing.The translating bearing serves to reduce effective friction parallel to the support plane and thus aids in achieving a stable grasp. One similarity to the pivoting gripper is that the additional degree of freedom does not require an active servo system. Also,both grippers were designed for application to parts feeding[6].

3The Pivoting Gripper Mechanism

Our idea for rotating parts requires two“hard?nger”con-tacts,which are de?ned as contacts that can apply forces pointing into the friction cone but cannot resist torques about the contact point[28].Clearly,a grasp with two hard?nger contacts cannot achieve form closure as the part is free to ro-tate about the contact axis.Indeed,[17]showed that4hard ?nger contacts are both necessary and suf?cient to achieve form closure on a polyhedron.However for feeding parts we do not require form closure;we want to insure that the part will not translate when lifted,and in contrast to most work on grasping,we want to insure that the part will rotate about the grasp axis.

One way to achieve hard?nger contacts is to use sharp-ened points.Such point contacts are sensitive to small vari-ations in part orientation and do not have the“self-aligning”bene?ts of?at contacts.Furthermore,point contacts may damage the part.To implement true hard?nger contacts, the biggest problem is eliminating frictional resistance to torques about the pivot axis.

We propose to use a bearing mechanism as illustrated in ?gure3.

An important consideration is that the bearing mechanism have a small footprint and also permit the pivoting axis to reach as close as possible to the worksurface to grasp small parts.Machining such a mechanism poses practical dif?culties.We machined our own bearing races and used custom needle bearings to build a prototype with footprint 1322mm permitting the pivot axis to be lowered to within 6mm of the worktable.We used?at-topped pencil erasers to provide high frictional resistance to translational forces. We mounted a pair of these bearings on a commercial pneumatic parallel-jaw gripper.When the jaws are closed under air pressure,compressive forces tax our thrust bear-ings and introduce frictional resistance to rotation.Fortu-nately,we have found that it is a simple matter to achieve compliant rotation by brushing parts against a?xed“lip”in the environment.The brushing movement can be achieved with a combination of vertical and horizontal movements of the arm,thus requiring no actuation at the pivot.

4The Parts Feeding System

Our feeder design is based on a commercially-available sys-tem that integrates machine vision with a high-speed robot arm.The system is programmed based on the type of part to be fed.During operation,a collection of like parts are

dropped and randomly scattered on a?at worktable where they are subject to the force of gravity.A set of conveyor belts is used to singulate parts and transport them into the ?eld of view of an overhead camera.Note that in general, parts will only have a?nite number of stable poses under the in?uence of gravity.Each of these is treated as a unique pattern by the vision system,which identi?es each pattern and its pose(position and orientation).Each pattern indexes into a pre-programmed manipulation routine for the pivot-ing gripper which picks up the part,reorients it if necessary, and moves it into a desired?nal pose.The process is then repeated for all parts that can be identi?ed by the vision sys-tem.Remaining parts are recycled for another pass through the system.

We implemented a prototype system in our laboratory using a commercially-available robot system:Adept604-S SCARA type arm,standard CCD camera,and Adept’s AIM vision software.Figure4shows a photo of the system in our laboratory.In one case we placed registration marks on the parts to cope with ambiguous and symmetric poses(one method for locating such marks is described in[24]).We also used diffused overhead lighting to reduce shadows and specularities.

In our initial experiments,we hand-singulated the parts by dropping them one-by-one into the camera’s?eld of view. We also hand-coded the grasp points for each pattern.After the robot reorients the part and places it into a pallet,it returns to a home position and waits for the next part to be dropped into its?eld of view.We tested the system with two sets of parts:rectangular parts made of steel and

orange insulating caps made of plastic.The latter parts were suf?ciently lightweight that gravity did not provide suf?cient torque to overcome friction;in this case we brushed parts past a?xed lip to achieve the same effect.

The resulting system worked quite reliably.We achieved feed rates of5seconds per part,including visual recognition of pose.In an industrial setting,the vision and manipulation can be pipelined to speed operation.The system was able to successfully feed parts about90%of the time.Failures were typically due to errors in visual recognition,grasp location, or incomplete pivoting along the lip.A videotape of these experiments is available.

5Comparison with Existing Feeders

Our goal is to develop a programmable system that ef?-ciently feeds a broad class of industrial parts.Parts to be fed will be singulated with the aid of vibration and a series of conveyor belts traveling at different speeds;parts that are not recognized or are unable to be reoriented will be rejected and recirculated.

This design for a programmable feeder offers the follow-ing advantages over previous methods:

Fast set-up and changeover:The camera,robot arm, and gripper can be used for a wide variety of part shapes.To set-up for a new part,only the vision and manipulation routines must be changed.

Figure4:Experimental system in our laboratory.

Less damage to sensitive parts:The proposed feeder is highly suited for delicate parts such as electronic or optical components.

Compatibility with large and small parts.Vibratory bowls are generally limited to parts of diameter?ve inches or less due to restrictions on bowl diameter.

Less Likely to jam:No mechanical?lters are required.

Lower Noise.OSHA Noise limits are90dBa,maxi-mum employee exposure over eight hours.Shrouds to contain noise can add up to25%to the cost of vibratory bowls[39].

This feeder design is not intended as a universal panacea. The initial investment for the?rst feeder will be higher than that for conventional(hard-tooled)feeders.And certainly conventional feeders will be more cost effective for high-volume parts such as fasteners and washers.But our hunch is that the?exibility of the vision-based system will be cost effective in the long run for a variety of industrial applica-tions.

6Planning Algorithms

To con?gure such a system for a new part,two changes in software are required:vision and manipulation routines.In our initial experiments the former was programmed using proprietary statistical decision software from Adept,and the latter was hand-coded.We are now working to develop plan-ning algorithms for automatically programming the system based on part geometry.

Given a CAD model of a part and its center of mass, the?rst step is to determine all of the part’s stable poses under the force of gravity.For polyhedral parts,we can compute the convex hull of the part and check if the center of mass projects into each face.Clearly,a polygonal part with faces can have no more than stable poses.For more general classes of curved parts,we are working with Dave Kriegman to build on a recent algorithm described in[14]. Each stable pose presents a projective image that can be identi?ed by the vision system.Well-known methods exist for automatically generating shape recognition rou-tines(some of these have been incorporated into Adept’s commercially-available software).We are also studying al-gorithms for automatically locating registration marks to reduce ambiguities.

A primary challenge is to develop algorithms that,given a CAD model of a part,will automatically plan appropriate grasp strategies for each stable pose.Given polyhedral part shape and coef?cient of friction as input,the problem is to ?nd a(possibly empty)set of grasps that will achieve the following objectives[25]:

The line connecting these contacts(the contact axis)is parallel to the worktable(due to the limited kinematics of the robot arm),

The part will not slip as it is lifted off of the plane,

The part will rotate about the contact axis as it is lifted due to the force of gravity and come to rest such that:

When the part is replaced on the table it will assume the desired pose.

Automatic planning software would permit of?ine analy-sis of the“feedability”of a proposed part,thereby providing designers with rapid feedback[38].It may also be possible to to predict feedrates of?ine using a probabilistic analysis of pose stability,ie,system feedrate is related on the proba-bility that a part will land on each of its stable faces[20,7]. We have implemented a method similar to that presented in [2],which starts with the convex hull of the part.Each face of this hull is projected onto a unit sphere centered on the part’s center of mass.This projected face de?nes a“cap-ture range”,a set of contact orientations that will converge on enclosed face as the part falls under quasi-static condi-tions.An2implementation is described in[37].We acknowledge that more accurate prediction of pose proba-bilities would require us to model the complex dynamics of frictional collisions which is notoriously dif?cult[18].

Many variations of the above system are possible.We might also include an active clutching mechanism for lock-ing the pivot when part rotations are undesirable.This would,for example,allow the same gripper to be used for feeding and inserting parts.

The system described in this paper is an example of what might be called a“RISC”approach to industrial robotics: R educed I ntricacy in S ensing and C ontrol[4].The idea is to reduce complex manipulations to a sequence of primitive operations that can be performed with simple mechanisms such as the pivoting gripper.A challenge is to develop robust planning algorithms that will automatically perform this reduction.We believe that such algorithms can have near-term application to manufacturing. Acknowledgements

We thank Tony Lewis,Mark Dane,and Dave Kriegman for their suggestions.We also thank John Elder for the photographs and Maria Wiegley for Figure2.

References

[1]John Birk.A computer-controlled rotating-belt hand

for object orientation.IEEE Trans.on Systems,Man, and Cybernetics,4(2),March1974.

[2]G.Boothroyd,A.H.Redford,C.Poli,and L.E.Murch.

Statistical distributions of natural resting aspects of parts for automatic handling.SME Manufacturing En-gineering Transactions,1:72,1972.

[3]Geoffrey Boothroyd,Corrado Poli,and Laurence E.

Murch.Automatic Assembly.Marcel Dekker,Inc., 1982.

[4]John Canny and Ken Goldberg.“RISC”for in-

dustrial robotics:Recent results and open prob-lems.In International Conference on Robotics and Automation.IEEE,May1994.Also available as USC Techreport IRIS-93-315and via anonymous ftp from128.125.51.19under pub/Tech Rept/Iris/1993/IRIS93315.ps.Z.

[5]Gregory T.Farnum and Bill Davis.Delivering the part.

Manufacturing Engineering,March1986.

[6]Ken Goldberg.Orienting polygonal parts without sen-

sors.Algorithmica,10(2):201–225,August1993.Spe-cial Issue on Computational Robotics.

[7]Ken Goldberg and Matthew T.Mason.Bayesian grasp-

ing.In International Conference on Robotics and Au-tomation.IEEE,May1990.

[8]Jerry Goodrich and Gary Maul.Programmable parts

feeders.Industrial Engineering Magazine,May1983.

Reprinted in Automated Assembly,Jack https://www.wendangku.net/doc/b817757931.html,ne ed., published in1986by SME.

[9]D.D.Grossman and M.W.Blasgen.Orienting me-

chanical parts by computer-controlled manipulator.

IEEE Trans.on Systems,Man,and Cybernetics,5, 1975.

[10]J.Hartley.Picking parts from a bowlfeeder with image

sensing.Sensor Review,1(1),January1981.

[11]J.W.Hill.Programmable bowl feeder design based on

computer vision.Assembly Automation,1(1),Novem-ber1980.

[12]Hajime Hitakawa.Advanced parts orientation sys-

tem has wide application.Assembly Automation,8(3), 1988.

[13]Ichiro Kato and Kuni Sadamoto.Mechanical Hands

Illustrated(Revised Edition).Hemisphere Publishing Corp,NYC,1987(originally published in1982). [14]David https://www.wendangku.net/doc/b817757931.html,puting stable poses of piece-

wise smooth objects.CVGIP:Image Understanding, 55(2),March1992.

[15]Jean-Claude Latombe.Robot Motion Planning.

Kluwer Academic Press,1991.

[16]Tomas Lozano-Perez,Joe Jones,Emmanuel Mazer,

and Pat O’Donnell.Handey:A Robot Task Planner.

MIT Press,1992.

[17]Xanthippi Markenscoff,Luqun Ni,and Christos H.

Papadimitriou.The geometry of grasping.IJRR,9(1), February1990.

[18]Matthew T.Mason,Ken Goldberg,and Y u Wang.

Progress in robotic manipulation.In15th Grantees Conference on Production Research and Technology.

National Science Foundation,January1989.

[19]Paul Moncevicz,Mark Jakiela,and Karl Ulrich.Orien-

tation and insertion of randomly presented parts using viratory agitation.In ASME3rd Conference on Flexi-ble Assembly Systems,September1991.

[20]L.E.Murch and G.Boothroyd.Prediction ef?ciency

of parts orienting system.Automation,2,1971. [21]James L.Nevins and Daniel https://www.wendangku.net/doc/b817757931.html,puter-

controlled assembly.Scienti?c American,1978. [22]Richard Paul.Modelling,Trajectory Calculation,and

Servoing of a computer Controlled Arm.PhD thesis, Stanford AIM-177,November1973.

[23]D.Pherson.Programmable feeder for non-rotational

parts.In15th CIRP International Seminar on Manu-facturing Systems,1983.

[24]Anil Rao and Ken Goldberg.Placing registration

marks.IEEE Transactions on Industrial Electronics, Special Issue on Industrial Robotics,1993.Accepted May1993.A preliminary version appeared in the1993 IEEE International Conference on Robotics and Au-tomation,Atlanta,GA,and as USC IRIS Technical Report293,April1992.

[25]Anil Rao and Ken Goldberg.Planning grasps for a

pivoting gripper.Technical report,USC Institute for Robotics and Intelligent Machines,https://www.wendangku.net/doc/b817757931.html,C Techreport IRIS-93-313.[26]A.H.Redford and E.Lo.Robots in Assembly.Halsted

Press,New Y ork,1986.

[27]Frank J.Riley.Assembly Automation,A Management

Handbook.Industrial Press,New Y ork,1983. [28]J.Kenneth Salisbury.Kinematic and Force Analysis

of Articulated Hands.PhD thesis,Department of Me-chanical Engineering,Stanford University,May1982.

published in it Robot Hands and the Mechanics of Manipulation,MIT Press,1985.

[29]Ben-Zion Sandler.Robotics:Designing the Mecha-

nisms for Automated Machinery.Prentice Hall,1991.

Chapter7summarizes results originally published(in Russian)in A.N.Rabinovitsh,Automatic Orientation and Parts Feeding,Technika,1968.

[30]Berhard J.Schroer.Electronic parts presentation using

vibratory bowl feeders.Robotics,3,1987.

[31]Neil C.Singer.Utilizing dynamic and static stability

to orient parts.Master’s thesis,MIT,1985.

[32]Neil C.Singer and Warren Seering.Utilizing dynamic

stability to orient parts.Journal of Applied Mechanics, 54,1987.See also Singer’s1985MIT Masters Thesis.

[33]T.Suzuki.An approach to a?exible part-feeding sys-

tem.In1st International Conference on Assembly Au-tomation,1980.

[34]Russ H.Taylor.A Synthesis of Manipulator Control

Programs from Task-Level Speci?cation.PhD thesis, Stanford AIM-282,july1976.

[35]Pierre Tournassoud,T.Lozano-Perez,and E.Mazer.

Regrasping.In International Conference on Robotics and Automation.IEEE,May1987.

[36]S.S.M.Wang and Peter Will.Sensors for computer

controlled mechanical assembly.Industrial Robot, March1978.

[37]Jeff Wiegley,Anil Rao,and Ken https://www.wendangku.net/doc/b817757931.html,put-

ing a statistical distribution of stable poses for a poly-hedron.In The30th Annual Allerton Conference on Communication,Control,and Computing.University of Illinois at Urbana-Champaign,October1992. [38]Randy Wilson and Jean-Claude Latombe.Reason-

ing about mechanical assembly.In The30th Annual Allerton Conference on Communication,Control,and Computing.October1992.

[39]Richard D.Zimmerman.Updated art–parts feed-

ing.In Assemblex VIII Conference.SME,March1982.

Reprinted in Automated Assembly,Jack https://www.wendangku.net/doc/b817757931.html,ne ed., published in1986by SME.

九年级课文翻译完整版

九年级课文翻译 Document serial number【NL89WT-NY98YT-NC8CB-NNUUT-NUT108】

人教版初中英语九年级U n i t3课文翻译 SectionA2d 何伟：这是欢乐时光公园——我所在城市最大的游乐园！ 艾丽斯：要尝试一些乘骑项目，我好兴奋呀！ 何伟：我们应该从哪里开始玩呢？有太空世界、水上世界、动物世界…… 艾丽斯：哦，你能先告诉我哪儿有洗手间吗？ 何伟：什么休息室你想要休息吗但是我们还没有开始玩呢！ 艾丽斯：哦，不是，我的意思不是休息间。我的意思是……你知道的，卫生间或盥洗室。何伟：嗯……那么你是指……厕所？ 艾丽斯：正是！对不起，也许“洗手间”一词在中国不常用。 何伟：对，我们通常说“厕所”或“卫生间”。就在那边。 艾丽斯：好的，我会很快的！我想知道公园今天何时关门。 何伟：九点三十，你不必着急！ SectionA3a 欢乐时光公园——永远快乐的时光 [艾丽斯和何伟在太空世界。] 艾丽斯：我想知道我们接下来应该去哪里？ 何伟：那边那个新项目怎么样？ 艾丽斯：好吧……看起来蛮吓人的。 何伟：快来吧！我保证它将激动人心！如果你害怕，只要大叫或者抓住我的手。 [云霄飞车之后……] 艾丽斯：你是对的！太有趣了！起初我好害怕，但大声喊叫还蛮管用的。 何伟：瞧，那玩意并不糟糕，对吧？某些东西你不去尝试，就绝不会知道。 艾丽斯：对，我很高兴我试过了！ 何伟：你现在想去水上世界么？ 艾丽斯：好，但我很饿。你知道我们在哪里能吃到好的快餐？ 何伟：当然！我建议在水上世界的水城餐馆，那里有美味可口的食物。 艾丽斯：好极了！我们走！ [在前往水城餐馆途中，艾丽斯和何伟经过鲍勃叔叔餐馆。] 艾丽斯：看！这家餐馆看起来蛮有趣的。这招牌上说这儿每晚有摇滚乐队演出。

雅思写作科技篇

科技 SCIENCE & TECHNOLOGY 在这部分，你的任务是： 一，背诵话题词汇短语 二，为题目列出英文提纲 基础词汇短语 advanced science 尖端科学 scientific invention 科学发明 exert a far-reaching impact on…对…产生一种深远的影响 double-edged sword 双刃剑 earth-shaking changes 翻天覆地的改变 pay the way for the future development 为未来的发展铺平道路 lay a solid foundation for…为…打下良好的基础 energy crisis 能源危机 depletion of resources 能源消耗 milestone 里程碑 sophisticated equipment 尖端设备 technical innovation 科技创新 expediency 权宜之计 antithetical 与…背道而驰的 over-commercialized 过渡商业化的 a heated discussion 热烈的讨论 exhaust gas 废气 disastrous 灾难性的 overshadow 使…相形见绌 compared to/with…与…相比 usher in 引领 speedy and comfortable 既快捷又舒适 opposite forces 负面影响 a fatal breakdown 致命故障 potential hazards 潜在危险 pose a threat to…对…有一种威胁 promote relative industries 促进相关产业发展 accelerate 加速… means of transportation 交通方式 transportation tools 交通工具 social status 社会地位 environmentally-friendly resources 环保的能源 make people's life easier 使人们生活更方便 alternative fuel 可替代燃料

关于运动的英语演讲稿

关于运动的英语演讲稿 篇一：英语演讲运动sports 英语演讲运动sports All over the world people enjoy sports. Sports help to keep people healthy and happy, and to live longer. Sports change with the seasons. People play different games in winter and summer. Swimming is fun in warm weather, but skating is good in winter. Some sports are so interesting that people everywhere go in for them. Football, for example, has spread around the world. Swimming is popular in all countries near the sea or in those with many rivers. Some sports or games go back thousands of years, like running or jumping. Chinese wushu, for example, has a very long history. But basketball and volleyball are rather new. People are inventing new sports or games all the time. Water skiing is one of the newest in the family of sports. People from different countries may not be able to understand each other, but after a game together they often become good friends. Sports help to train a

九年级英语unit课文翻译

九年级英语u n i t课文 翻译 Document serial number【KK89K-LLS98YT-SS8CB-SSUT-SST108】

unit3 Could you please tell me where the restroom are ? sectionA 2d 何伟：这就是欢乐时代公园——我们这座城市最大的游乐园。 爱丽丝：就要玩各种游乐项目了，我好兴奋呀！ 何伟：我们先玩那样呢？有太空世界、水世界、动物世界…. 爱丽丝：在我们决定前，麻烦你先告诉我哪儿有洗手间吗？ 何伟：什么？休息室？你想要休息了？我们可还没有开始玩呢！ 爱丽丝：不是的，我不是指休息的地方。我是说…..你知 道，一间洗手间或卫生间。 何伟：嗯….那么你是指….卫生间吗？ 爱丽丝：对啦！不好意思，也许中国人说英语不常用 restroom这个词。 何伟：就是的，我们常说toilets 或washroom 。不过，厕所在哪里。 爱丽丝：知道了，我一会儿就好！ 何伟：没问题，你不必赶的。 Section A 3a 欢乐时代公园————总是欢乐时光 [ 爱丽丝和何伟在太空世界] 爱丽丝：我不知道我们接下来该去哪里。

何伟：去玩玩那边那个新项目怎样？ 爱丽丝：啊…..看上去挺吓人的。 何伟：勇敢些！我保证会很好玩！如果害怕就喊出来或抓住我的手。 【乘坐后…..】 爱丽丝：你是对的，这真好玩！我起先有些害怕，但喊叫真管用。何伟：瞧：这并不糟糕，对吧？你需要去尝试，否则永远不会知道你能行。 爱丽丝：是这样的，我真高兴自己尝试了这个项目。 何伟：现在你想去水世界吗？ 爱丽丝：当然，但我饿了。你知道哪里有又好吃又快的地方？ 何伟：当然知道！我建议去水世界的水城餐馆他们做得很好吃。爱丽丝：太好了，我们去吧！ 何伟：[在去水城餐馆的路上，爱丽丝与何伟路过鲍勃叔叔的餐厅]爱丽丝：你瞧！这间餐厅看上去很有意思。牌子上写着有个摇滚乐队每晚在演奏。 何伟：我们为何不回头过来在这吃晚饭？咱们去问一下乐队演出几点开始。 【爱丽丝和何伟向门口的员工走去】 爱丽丝：劳驾，请问你们乐队今天晚上何时开始演奏？ 何伟：八点。那时人总是很多，所以得来早一点才有桌子。 爱丽丝：好的，谢谢！

关于科技的英语演讲稿Technologyand

关于科技的英语演讲稿—Technologyand thepresenceofstudents,ladiesandteachers,everyone!iw aspreparedintervalsofcloudtoday,inhonorhereentitled“te chnologyandfuture”speech,iamveryproudofboth,butsomeune ase.inrecentyears,wehaveseenourgreatmotherland,thecause oftherapiddevelopmentoftechnology,whichallowmetoachines eifeelveryproud.rememberthatlongago,cellphoneusealmostt heonlyone,whichiscalled,butafewyearsago,cellphoneshasun dergonegreatchanges,notonlylookmorebeautiful,butalsouse more,youcanusethephonestotakepictures,meetings,internet ,textmessages,etc.aseriesofthingsthatitheirlifemoreconv enient,soiammoreawareofthestrengthofthetechnology,butia mjustafledglingsstudents,“technology”asthewordalsoawa reofthelimited,iamunabletousesomeverydifficulttheorytoe laboratetechnologyxuanji,norighttoworkontheireldersican promiseofthetechnologyblueprint.butiamwillingtouseastud ent’sperspectivetotheimaginetechnologyandthefuture.fromgene ticengineering“isaliveprinces”dream,nano-technology“

雅思写作素材Technology & media

Technology & media 类 科技类 People today can perform the everyday tasks such as shopping, banking or even business transactions, without meeting others face-to-face. What effects will this phenomenon have on individuals and society as a whole? 开头段（不少于3+1句） The interactivity of the Internet and the mobile phone has enabled a multitude of people to purchase their desired items or pay their phone bills without stepping out of their offices or homes. And many others can even register for tests or sign contracts online. This sweeping trend of going about everyday business in the virtual world has triggered a marked decline in face-to-face contact between people. Thus, it is essential that we identify the implication of this trend on both individuals and society as a whole. 主体段1（不少于1+6句） The impact of this phenomenon on individuals is profound. First, Individual efficiency in business transaction and banking will be greatly enhanced. And those who dread shopping are spared the chore of browsing around in shops. Secondly, the increasingly sedentary lifestyle will engender a higher incidence of ailment. More overweight people means more patients suffering from cardiovascular diseases such as vein hardening, diabetes and hypertension. Thirdly, the absence of face-to-face contact may induce distrust between business partners. An inherent sense of disbelief is apt to ruin a telecommunicated negotiation when negotiators can only see videos of each other transmitted via the Internet. 主体段2（不少于1+6句） This trend also has widespread repercussions on society as a whole. In the first place, the burgeoning e-commerce will, doubtless, boost corporate efficiency immeasurably. And higher efficiency means more earnings and less costs for businesses. In the second place, online fraud, be it banking or trading, retail or wholesale, is sure to abound in the cyberspace. We must search for practicable and effectual means of curbing it. In the third place, the proliferation of e-commerce may exacerbate man's overdependence on technology. And that can render our lives unspontaneous and our tempo of life too fast and furious. 结尾段（不少于2句）

英语演讲稿：我喜欢运动

英语演讲稿：我喜欢运动 my favourite sport good afternoon, ladies and gentlemen. it’s my great pleasure to be here sharing my speech with you. today my topic is my favourite sport. look at my healthy skin , oh! can you guess which sport i like best? yes,it's swimming !that's why i look so handsome. when i was only 5 years old, i began to learn how to swim and i like it. i think swimming is an interesting sport and it's exciting. it's also a good way to keep fit . every summer, i go to swimming school . my parents say i’ll have a good health if i insist swimming in a right way. and i can grow taller if i go to swim often. so i always ask my coach some questions on swimming and he always helps me a lot. i can swim so well and i can swim breaststroke, backstroke and freestyle. if you also like swimming, join me! thank you! 我最喜欢的运动

英语新课标九年级课文翻译Unit9-14

英语新课标九年级课文翻译Unit9-14 Unit9 I like music that I can dance to. SectionA 2d 吉尔:斯科特,周末你打算干什么呢? 斯科特:没什么事,我估计就是听听我新买的激光唱片吧. 吉尔:哦?是什么激光唱片? 斯科特:嗯,全是音乐的,没有歌曲。我喜欢听舒缓的音乐来放松自己,尤其是在工作了漫长的一周以后。 吉尔:听起来不错啊。嗯,如果你有空,愿意和我一起去看部电影吗?(电影的)导演很有名。 斯科特:嗯,那要看什么电影。我只喜欢有趣的电影,我只想笑一笑不想费脑筋,你懂我的意思吧? 吉尔:哦,那样的话,我还是去邀请喜欢看严肃电影的人吧. 斯科特:(你说的)电影是关于什么的? 吉尔:是关于第二次世界大战的。我喜欢能让我思考的电影。 section A, 3a 今天你想看什么(电影)呢? 虽然一些人坚持只看一种电影,但是我喜欢看不同种类的电影,(具体)由当时盼心情决定。 当我情绪低落或感到疲惫的时候,我更喜欢能让我开心的影片。比如,像《黑衣人》那样的喜剧片或像《功夫熊猫》这类的动画片,通常都有滑稽的对话和一个愉快的结局。影片中的人物不一定完美,但是他们都会尽力去解决问题,看了这样的电影,我所面对的许多问题突然间会显得不那么严重,我也会感觉好多了。两个小时的欢笑是一种很好的放松方式。 当我伤心或劳累的时候,我不看剧情片或纪录片。像《泰坦尼克号》这样的剧情片只会让我更伤心。像《帝企鹅日记》这样的纪录片,(通常)会针对某个特定话题提供丰富的信息,(内容)也很有趣,但是当我累的时候,我不想思考太多。当我太累不想思考时,我不介意看像《蜘蛛侠》这样的动作电影。我只想屏蔽我的大脑,坐在那里观看一个令人兴奋的超级英雄,他总是能在关键时刻挽救世界。 偶尔我会喜欢看恐怖片。虽然它们很有意思,但是我会因为太害怕而不敢独自一人看,我总会带上一位不怕这些类型的电影的朋友(一起看),这样就觉得没那么可怕了。 Secton B 2b 凄美 昨晚我的一个中国朋友带我去听了一场中国民间音乐会。其中有一首二胡曲令我特别感动。音乐出奇的美,但是在那美的背后,我感受到悲伤和痛苦。这首曲子有个简单的名字,《二泉映月》,但它是我听到过的最感人的曲子之一。二胡(的声音)听起来那么悲伤,以至于我在听的时候也几乎随着它哭了。后来我查阅了《二泉映月》的历史,开始理解音乐中蕴含的伤感。 这首曲子由一位民间音乐家阿炳写成,他于1893年出生在无锡市。在他还很小的时候,他的母亲就去世了。阿炳的父亲教他弹奏各种乐器,如鼓、笛子和二胡。到了十七岁,阿炳就以他的音乐天赋闻名。然而,他的父亲去世后,阿炳的生活变得更糟糕。他很穷,还得了很严重的疾病,眼睛瞎了。好些年他都没有家,他住在大街上,以弹奏音乐来谋生。即使在他结了婚有了家以后,他还是继续在街道上唱歌、弹曲,他以这种方式表演了好多年。 阿炳惊人的音乐技能让他在有生之年就非常出名。到他临终前,他已会弹六百多首曲子,大部分是他自己写的。遗憾的是,一共只有六首曲子被录了下来得以传世,但时至今日,他(的作品)依旧颇受人们喜爱。今天,阿炳的《二泉映月》成 了所有伟大的二胡演奏家弹奏和赞赏的曲子。它已成了中国文化魁宝之一。它的凄美不仅描绘出阿炳自己的生活,而且也让人们回想起自身的悲苦体验和最深的的痛。

雅思考试大作文范文四篇科技类

雅思考试大作文范文四篇科技类 网为考生们提供最新最全的雅思写作范文,希望对大家有帮助。 雅思大作文范文：电脑VS老师 It is witnessed that computer technology hasbrought human beings uncountable benefits and aneducational revolution seemingly can be expected hence a substitution of teachers in theclassroom. As to discuss this controversial issue, opinions vary from person to person. On the one hand, the teacher plays an important role as a supervisor as well as aconductor in the classroom (topic sentence).It is commonly believed that adolescents are tooyoung to distinguish the good from the bad and they need correct guidance from decentadults; otherwise, they might stray from the right way. Children are always easy to becomeaddicted to computer games, which have too much violent and pornographic propaganda.Without teachers' guidance, most children would spend hours playing fascinating games oncomputers instead of studying useful knowledge during school times. Moreover, a teacher in theclassroom may organize a discussion on a complicated or

英语比赛演讲：我喜欢运动-英语演讲稿

英语比赛演讲：我喜欢运动-英语演讲稿 my favourite sport good afternoon, ladies and gentlemen. it’s my great pleasure to be here sharing my speech with you. today my topic is my favourite sport. look at my healthy skin , oh! can you guess which sport i like best? yes,it’s swimming !that’s why i look so handsome. when i was only 5 years old, i began to learn how to swim and i like it. i think swimming is an interesting sport and it’s exciting. it’s also a good way to keep fit . every summer, i go to swimming school . my parents say i’ll have a good health if i insist swimming in a right way. and i can grow taller if i go to swim often. so i always ask my coach some questions on swimming and he always helps me a lot. i can swim so well and i can swim breaststroke, backstroke and freestyle. if you also like swimming, join me! thank you! 我最喜欢的运动

九年级英语课文翻译,帮忙

7楼 迪士尼乐园是个娱乐的公园，但我们也可以叫它“主题公园”。它拥有你在其他公园可以找到的所有的娱乐设施，但是它有一个主题。当然，这个主题就是迪士尼电影和迪士尼人物。比如说，在其他一些公园你可以看到到摩天轮，但是在迪士尼乐园，摩天轮就有了“迪士尼人物”的主题。这意味着你可以在摩天轮的任何地方看到迪士尼人物。同样，你也可以看有关迪士尼的电影，在迪士尼餐厅就餐，买迪士尼礼物。你还随时可以看到迪士尼乐园里来回走动的迪士尼人物！ 你听说过“迪士尼航行”吗？那是同样有迪士尼主题的巨大的船。你可以在船上航行几天，还可以在甲板上吃东西睡觉。和迪士尼乐园一样，甲板上也有许多吸引人的地方。你可以购物，参加迪士尼的聚会，和米老鼠一起吃晚餐。这些船有几条不同的航线，但最终都会抵达同样的地方。那就是属于迪士尼乐园的小岛。 在迪士尼乐园的乐趣简直太多了！ 9. p72 UNIT 9 3a: Come to the Hilltop Language School and change your life. 来到Hilltop语言学校,改变你的人生! 第一篇:这里是两名同学讲述关于我校的事情 当我还是个小女孩,我就梦想着去旅行,因而我选择了个最佳的方式—从事空中乘务员.我做这个行业已有两年了,它的确是份有趣的工作,我能游遍世界各地,但也我发现说好英语对我来说是件多么重要的事,正因如此早在当空乘之前我就在Hilltop语言学校学习五年了,我以一口流利的口语赢得了这份工作,谢谢, Hilltop语言学校! Mei Shan 第二篇: 我渴望当一名导游,事实上,这是我一直都很想要从事的事业.我渴望旅行,特别是英语国家,像是美国,澳大利亚.不论如何我知道我必须提高我的英语能力,于是我来到Hilltop语言学校进行口语学习, Hilltop语言学校对我的学习有很大的帮助,我已经在这里学满一年了,非常热爱这个地方.或许当我要离开这个学校的时候,我开始想做一名英语教师的热情会大过于想做一名导游! David Feng 9. p74 UNIT 9 3a: Have you ever been to Singapore？翻译！ 你去过新加坡吗？ 对于很多中国旅游者来说，这个位于东南亚的小岛是个度假的好去处。一方面，超过四分之

雅思A类大作文真题范文：远程医疗

2018-06-02: Task 2 (India) Some people use technology to take advice for their medical problems rather than seeing to doctor. Why is this so? Is it positive or negative development according to you? 范文1： Owing to technology, everything becomes easily accessible. Some people take advantage of technology as they discuss their health issues with experts on the internet rather than going to them. This trend increasing in our society as people have a busy schedule. In my opinion, it is a positive development as taking medical prescription online save time as well as energy. But it has some disadvantages also so discussed below. Technology brings people close enough that they can discuss their problems with a number of people at once and can share their experiences so that others can take advantage of this. Taking online prescription save time, as there is no need to run to the hospitals and set a queue to meet the doctors. Using technology, people can take advice from foreign experts rather than considering only native ones. Various online websites are now available, where experts and people can communicate with each other, here https://www.wendangku.net/doc/b817757931.html, is worth mentioning as it provides a common platform for everyone. However, it may have some disadvantages, as in serious health issues such as cancer or in other deadly diseases where the doctor can visually check and do some tests, is not possible online. In those cases, people should visit the experts and get proper medical care. Under specialist vision, the patient gets recover much faster. Although technology provides us various advantages, sometimes under certain circumstances, it may worsen the situation. For example, in case of heart attack patient should rush to the hospital rather than taking online medical care. In some medical issues such as cold, fever people should take advice online but in other deadly cases, people should visit to doctors so that can take better medication. In conclusion, no doubt technology has a huge role and brings everything closer, it has its own merits and demerits, we can take only certain medication and healthcare pieces of advice such as what we should eat to reduce the weight, not in other serious issues. 范文2： Many individuals are making use of technology such as the internet to seek medical advice instead of visiting a doctor. There are many reasons behind this, however, in my opinion, it is a negative development.

关于运动英语演讲稿

关于运动英语演讲稿

关于运动英语演讲稿 【篇一：英语演讲运动sports】 英语演讲运动sports all over the world people enjoy sports. sports help to keep people healthy and happy, and to live longer. sports change with the seasons. people play different games in winter and summer. swimming is fun in warm weather, but skating is good in winter. some sports are so interesting that people everywhere go in for them. football, for example, has spread around the world. swimming is popular in all countries near the sea or in those with many rivers. some sports or games go back thousands of years, like running or jumping. chinese wushu, for example, has a very long history. but basketball and volleyball are rather new. people are inventing new sports or games all the time. water skiing is one of the newest in the family of sports. people from different countries may not be able to understand each other, but after a game together they often become good friends. sports help to train a persons character. one learns to fight hard but fight fair, to win without pride and to lose with grace. (胜不骄,败不馁) [点评] 运动是人人皆知的话题。作者从运动的种类到运动项目的历史作了一番描述，在结尾段中强调了运动的好处，观点显而易见。语言简单明了，描述、议论清楚。 [参考译文]

人教版九年级英语课文全册翻译

人教版九年级英语课文翻译 一单元 SECTION A 1a 我通过制作抽认卡来学习。通过和朋友一起学习。通过听磁带。通过做抽认卡。通过向老师求助。通过读课本。通过制作单词本。 1c A：你怎么为考试而学习。B：我通过参加学习小组来学习。 2a 1、你是通过看英文录像学英语的吗？ 2、你曾和朋友们练习过对话吗？ 3、听磁带怎么样？ 4、大声朗读以练习发音怎么样？5、我曾经通过参加学习小组的方式学习过吗？ 2b A是的，我通过那种学习方式学到了很多。B、哦，是的，它提高了我说英语的能力。C、有时那样做。我觉得他有用。D、不。（通过看英语录像学习）太难了，无法理解录像中的人所说的话。 2c A你曾经通过参加学习小组来学习吗？B、是的，我参加赤字，通过那种方式我学到了很多。 Grammer Focus 你怎么为准备一场考试而学习？我靠听磁带。你怎样学习英语？我通过参加学习小组来学习。你通过大声朗读来学习英语吗？是的，我是。你曾和朋友们练习过对话吗？哦，是的，他提高了我说英语的能力。你曾经通过参加学习？小组来学习吗？是的，我参加过。通过那种方式我学习到了很多。 3a如何才能学得最好 这星期我们询问了新星高中的同学关于学习更多英语的最佳方法的问题。许多同学说他们通过使用英语为学习它，一些还有很特别的建议。比如，李莉莲说学习新单词的最好的方法是阅读英语杂志。她说记忆浒音乐的歌词也有一些作用。当我们问及学习语法的问题时，她说：“我从不学习语法。它太枯燥了。” 魏明有不同的看法。他学习英语已经6年了，并且确实喜欢英语。他认为学习语法是学习一门语言的一种好方法。他还认为观看英语电影也不错，国灰他可以看到演员说话的情形。但是，有时候他发现看英语电影是件很头痛的事情，因为那些演员说话太快了。 刘畅说加入学校英语俱乐部是提高英语最好的方法。学生有很多练习的机会并且他们也有很多乐趣。她补充说和朋友练习会话一点用处也没有。“我们会因为某件事变得很激动，最后用汉语来讲，”她说。 3b A：我正在作一个关于学习英语的调查。我能问你一些问题吗？B：当然。A：太好了！你叫什么名字？B：魏明。A：那么你是怎样学习英语的，魏明？B：…… 4 A：你列词汇表吗？B：噢，是的。我常那样做。 SECTION B 1a我不会发其中一些单词的音。我不会拼写一些英语单词。我听不懂英语口语。我在语法上犯错误。我读得很慢。1b我不知道怎么使用逗号。 2a 1、不能正确发音。 2、忘记很多生词。 3、人们和我说话时我不能每次都听懂。 4、不能理解杂志中的单词。 5、没有获得很多写作训练。 2B A、你可以一直将生词写在你的笔记本里，并在家学习它们。B、你应该找一个笔友。C、听力能起作用。D、为什么不加入一个英语俱乐部来练习说英语呢？ 2C A：我没有搭档来练习英语。B、也许我应该加入一个英语俱乐部。 3a我是怎样学习英语的 去年英语课对我来说很难。首先，对我来说听懂老师说话很难。开始，她说的太快，我不能听懂每个单词，后来，我意识到如果你听不懂每个单词并没有关系。而且我害怕在班上说话，因为我认为同学们可能会嘲笑我。我也不是总能造出完整的句子。然后我开始看英文电视。那很有用。我认为做大量听力练习是成为一个好的语言学习者的秘决之一。另一件我觉得很难的事是英语语法。所以我决定在每节课上记大量语法要点。然后我开始用我正在学的语法自己写新句子。这样作用处之大令人惊奇。现在我很喜欢学英语并且这学期我得了个A。我的老师对我印象很深。作者觉学英语很难是因为……1、老师发音差。2、她说话时人们总是嘲笑她。3、她在造完整的句子方面有困难。4、英语语法很难。当她开始…她的英语提高了。5、和说英语的朋友一起出去。6、大量的听力练习。7、在自己组织的句子里使用语法。 3b 亲爱的，我知道学英语不容易，但我有一些想法可能有用。你说你不能理解说话太快的人。那么，你可以尽量听最重要的单词，而不是每个单词。 4 1、关于学英语什么不容易。2、就这一点你作了什么？3、你最喜欢的学习更多英语的方式是什么？韩文说如果人

关于科技的英语演讲稿—Technology(多篇范文)

关于科技的英语演讲稿—Technology 目录 第一篇：英语演讲稿—Technology and future 第二篇：英文科技转让协议范本Technology assignment agreement 第三篇：关于科技的英语演讲稿—Technologyandfuture 第四篇：演讲稿 modren Technology or traditional value 第五篇：what Technology brought us 科技给我们带来的影响正文 第一篇：英语演讲稿—Technology and future the presence of students, ladies and teachers： everyone! i was prepared intervals of cloud today, in honor here entitled Technology and future speech, i am very proud of both, but some unease. in recent years, we have seen our great motherland, the cause of the rapid development of Technology, which allow me to a chinese i feel very proud. remember that long ago, cell phone use almost the only one, which is called, but a few years ago, cell phones has undergone great changes, not only look more beautiful, but also use more, you can use the phones to take pictures, meetings, internet, text messages, etc.

科技作文之雅思大作文科技类

雅思大作文科技类 【篇一：雅思写作科技类满分范文解析,必看!】 雅思大作文考试题材多样，考生要想取得高分就要对每一种题材都有所了解并掌握技巧。今天，就以科技文为例，一起来学习雅思写 作科技类满分范文解析吧。相信通过学习，你会了解一篇满分作文 怎样写才会投考官所好，拿到满分。 科技类最常见的话题类型有两种： 1，科技产品评价及未来发展 即“科技产品怎么样，以后会怎么样”的问题;具体包括对现有科技产品的评价(优劣势分析、是否合乎道德标准和对个人、企业、国家以及整个社会的影响)和自己预想以后会出现什么样的产品或现有产品会出现什么样的功能以及未来的影响。 2，科技产品作为媒介 即“怎么用”的问题;具体包括现代通讯技术使人类足不出户便能操作网络购物、电视购物、网上银行、视频会议等，人类使用手机的利弊，互联网传播信息的好处与弊端，网上翻译软件盛行因此还有没 有学习外语的必要。 要评价一篇文章的优劣势，首先还是让我们熟悉一下writing task 2即大作文的评分标准。 (1) task response (tr) whether all parts of the task are addressed whether a viewpoint is clearly expressed, developed and supported. (2) cohesion and coherence (cc) whether the response has a suitable layout and logical ordering of points(文章是否条理清晰，行文有逻辑) correct and appropriate use of connectives (是否正确使用衔接词) (3) lexical resources (lr) range and accuracy of vocabulary (词汇丰富度和准确度) https://www.wendangku.net/doc/b817757931.html, the correct form and spelling of the words (词汇形式和拼写正确) (4) grammatical range and accuracy (gra) the range and accuracy of tenses and sentence structure (时态和句式的丰富度和准确度)