初三随堂练习(3月22日)

初三随堂练习（3月22日）

首字母填空解题技巧及专项训练

Step1：掌握七种句子成分与十种词性之间的对应关系。通过对单一成分的分类练习，掌

握该句子成分与何种词性相对应。词性正确是答案正确的前提。

(1) 对主语的判断

1. _______ are helpful to students. ( teach )

2. _______ is more important to me than money. ( healthy )

3. Some famous _______ are going to give lectures in our university in August. ( science)

4. _______ stamps is my hobby. ( collect )

分析：以上练习中，所填的词均为句子的主语。主语是动作的发出者，词性主要为名词与代词；动词不能

直接用作主语，必须转化成其对应的名词或动名词。此外，形容词前加the以及带连词的句子也可作主语。例如：

The rich are not always happy. 句中the rich 指“有钱人”，因此可以作主语。

What I wanted was just your help. 句中What I wanted是一个带有连词what的句子，因此也可以作主语。(2) 对谓语的判断

John was standing on the step of a house. An old woman c________ over to him. “My boy,” she a_____ , “Is your father at home?” “Yes,” a_______ John. The woman b________ ringing the bell. She rang and rang, but there was no answer. At last she t_____ back t o John and s______ angrily, “Didn’t you s______ that your father was at home?” “I did”, answered John, “but this i_______ my house.”

分析：语篇中的所缺词均为谓语动词。谓语是句子所表示的动作，词性只能是动词，而且在句子中不能缺。当一个主谓结构中同时出现两个或两个以上动词时，还要判断他们之间的相互关系，对谓语动词或非谓语

动词的判断只有在熟练掌握相关知识的基础上，才能作出正确的判断。平时多练习“用动词的适当形式填空”练习，有助于对动词形式的判断。

(3) 对宾语的判断

1. Mr. Chen was surprised to see the fast ________ in Shanghai after his long absence from the city. ( develop )

2. The front is in great need of medical _____.( work )

3. Thank you for your _______. ( kind )

4. At last he sold his ______. ( invent )

分析：宾语是动作的承受者，分动词宾语与介词宾语两种。宾语的词性同和主语的词性一样，但是如果代

词作宾语时就必须用其宾格。

(4) 对表语的判断

1. It is ______ for an ordinary plane to fly to the moon. ( possible)

2. The sick man is getting ______. ( ill )

3. Patrick is going to be a(n) ______ when he grows up.(engine)

4. Such cold weather is quite _____ in June and people have to wear warm clothes again. （ usually ）

5. It’s a ______ to have a picnic with all the members. （please ）

分析：表语是连系动词后接的成分。词性主要为形容词，名词, 介词短语。如果是动词的适当形式作表语，动词必须改成 to do ,doing 或 done 的形式。

(5) 对定语的判断

1. The _______ exams usually take place at the end of June. ( finally)

2. On a _____ night, you can see thousands of stars in the sky. ( clearly)

3. In ______ weather, the old had better stay at home. (freeze )

4. The French artist said, “It is my _____ time to visit Shanghai. I love this city so much. ( one )

5. Most people don’t like ________ food. ( freeze )

6. Who is your ________ teacher? ( chemical )

分析:定语是修饰名词与代词的成分。词性以形容词，序数词，介词短语为主。名词修饰名词说明后面名

称的性能或用途。如：stamp show / physics teacher。如果是动词的适当形式作定语，动词必须改成 to

do ,doing 或 done 的形式。

(6) 对状语的判断

1. The old lady could hardly believe that she had got the travel pass to Hong Kong so ______ (easy)

2. Watch ______, and you will find the difference between the two pictures. ( care )

3. After flying in the storm for nearly one hour, the helicopter landed ______ at last. ( safe )

分析：状语是说明动作发生的时间，地点，原因，方式，目的，结果，条件和伴随情况的成分。词性以副

词为主，也可以是介词短语。如果是动词的适当形式作状语，动词必须改成 to do ,doing 或 done 的形式。

(7) 对连词的判断

1. Work harder, __________ you’ll make great progress in English.

2. My job is to protect the innocent __________ find the guilty.

3. __________ you __________ he can go to the cinema, but you cannot go together because I have only one ticket.

4. Can you tell me _________ you are from?

5. I’ll give you a call __________ I get to Japan.

分析：在英语中, 并列连词and, but, or, so , not only…but also, either …or, neither…nor, as well as, both… and 等连接并列的词,词组和句子; 而从属连词则连接主句与从句。

Step2：在牢记了七种句子成分与十种词性的对应关系之后，多做综合的“用所给单词的正确形式填空”，有利于提高对句子成分的判断能力。熟练掌握词性转化的技巧是通向首字

母填空的第二步。

Step3：锻炼自己的发散和归纳思维的能力，或称为“猜谜”的能力。

Exercise : Guess the missing word.

1. ________ are helpful to students.

2. ________ are helpful to students. They give them knowledge.

3. ________ are helpful to students. In class they teach them knowledge and after

class they care for them like parents.

4. ________ are helpful to students. They keep them healthy.

Step4：对词性、词义、词形的精确判断阶段，即综合运用阶段。

Mr. Wu is getting old. He is l_______ the school soon. The s_______ in his class have given h______ a lot of

p_______. Among t______ are cards, note-books, photos and books. Most of the cards are m______ by the students themselves. Photos will h_____ Mr. Wu remember the happy t_________ when he was with his students. Next week, t________ will have a p_______ to s ______ goodbye to him.

Step5：熟能生巧阶段。要做到举重若轻，必须在前四步的基础上作长期系统的训练，把上述知识演化为解题技能。

Read the passage and fill in the blanks with suitable words .( 在短文的空格内填入适当的次,使其内容通顺. 每空格限填一词, 首字母已给 )

At one time, making a film was an expensive activity only for a small group of people and film companies. Not only were the tools and machines expensive but the cost of film was also far greater than most people could afford. However, modem technology has c 92 all that. New technology has really opened up the world of film-making for film fans. Now a camera does not cost m 93 and most young people are certainly able to pay for it. So all you need is to get one for yourself. With that, you may then start your own film-making.

However, film-making is t 94 work. You probably need many other people to help you.

For example, the p 95 of actors and actresses is very important in your film. Of course, these actors and actresses may be your schoolmates, friends or family members. You don’t even need to pay them a cent while they are glad to be part of your job.

B 96 , you need to make up a story. Can you write your own one? If you have good imagination, you can create an attractive story e 97 . Many world-famous film makers and producers are also good story-writers. If not, perhaps you need someone else to write it for you.

An excellent story is the key to making a s 98 film.

实战练习

（1） Sleep is not the same every night. We experience some deep sleep and some active

sleep(积极睡眠), which is when dreams happen. You might think sleepwalking(梦游) would happen in active sleep, but a person isn't physically active d 86 active sleep. Sleepwalking usually happens in the first few hours of sleep in the stage called slow-wave(慢波)or

deep sleep. Not all sleepwalkers a 87 walk. Some simply sit up or stand in bed or act like they're awake when, in fact, they're asleep! Most, however, do get up and move around for a few seconds or for as long as half an hour.

Sleepwalkers' e 88 are open, but they don't see the same way they do when they're awake and often think they're in different rooms of the house or different places altogether. Sleepwalkers tend(往往会) to go back to bed on their own and they won't r 89 it in the morning. Doctors say sleepwalking sometimes occurs when a person is sick, has a fever, is

not getting e 90 sleep, or is stressed. If sleepwalking occurs frequently, every night or so,

it's a good idea for your mom or dad to take you to see your doctor. But occasional(偶然的) sleepwalking generally isn't something to worry about, a 91 " it may look funny or even scary (惊恐的) for the people who see a sleepwalker in action.

It's important, of course, that the person is kept safe. Precautions(预防措施) should be t 92 so the person is less likely to fall down, run into something, or walk out the front door while sleepwalking.

（2）Everyone needs sleep. In fact, all living things need sleep. Having a sound and good rest m_____86_____ us healthy. It is believed that our brain develops best during sleep. It helps all our systems work well w_____87_____ we are awake. Sleep allows our brain to reorganize all events during the day and will improve our memory development.

For a student, eight to ten hours of sleep is required to give him or her e_____88_____ for the following day. A good sleep allows them to grow physically and mentally (心理上).

With e_____89_____ sleep at night, students would be able to wake up early and be ready for school activities. They will be able to listen carefully in class and would have the ability to memorize the things that they learn and r_____90_____ them in the future.

Eight hours of sleep makes students active t_____91_____ the whole day at school. They would be able to perform well in class, take down notes and finish their homework. When they have slept well, they can e_____92_____ understand their lessons. Good sleep prepares them well for the challenges (挑战) at school, from paperwork to sports. They will be ready to solve difficult tasks that require mental ability and skills.

（3）Anger (生气) is a kind of feeling. Many things can make you angry. When your teacher gives you too much homework, when your team loses an important game, when your friend b __86__ your favourite thing and then breaks it, you may get really angry.

Usually, your body will tell you when you are angry. For example, you breathe much

f__87__, your face turns red and you may want to break something or hit someone, but sometimes, you hide your anger. For example, you may hide it in your h__88___ . The problem is that if you do this, you may get a headache or your stomach may hurt.

In fact, it's not good to hide your anger, and it's normal for you to get angry sometimes. But anger must be let out in the right way, without hurting o_ 89 _or yourself. Let me give you some advice.

When you get angry, you can talk about it with other people. It's helpful to talk about your anger with other people, such as p___90____, teachers, good friends etc. When you talk about anger, those b___91___feelings can start to go away. On the other hand, when you start to feel angry, you can do some other things: count from 1 to 100; go for a bike ride; think about good things, etc.

Don't let your anger c 92 you. Remember that how you act when you are anger can make everything better or worse.

（4）In the middle of the 1800s, France was considered the most important place in the world for art. One reason for that was the Academy, a government organization with some strict r__86_ ___ about art. It decided what could and could not be art. In order to be accepted by the Academy, an artist had to be very talented. Artists also had to paint exactly the way the Academy wanted them to. A brave group of painters challenged(挑战)these ideas and changed art f_87___

Each year, the Academy had an exhibition of the art they had decided was the best. In 1864, a group of artists became a ___88____ because they didn’t get into the show. They felt that their paintings were not bad; the paintings were just different. After complaining to the government, these artists were given their own show.

The Academy thought all art should look realistic(逼真).But these artists were more interested in trying to show movement and the bright colors of daylight. In their opinion, it was more real to show these than it was to paint a scene(场景)which was as s_89___as a photo. It was also more interesting to show all of the different colours when light hits an object like water.

By 1874, many different artists were painting in this new style, including Claude Monet. One of his paintings had the title, Impression: sunrise. A critic(评论家)h__90__these new artists. He used Monet’s title to make fun of these painters by calling them“Impressionists（印象派）”，meaning that they didn’t make real paintings. The critics who liked these artists thought the word was just right. They began to use it happily. They thought it was more important to paint h_91__they saw things instead of just what they saw. Other artists around the world felt that they could have this freedom as well. Because of the impressionists, the art w_92___was never the same.

中考九年级初三英语专项训练七选五练习(含答案)

七选五练习 1、Lana went to see a new movie in the morning. But she didn't enjoy it. She's talking to Jenny about what happened. Jenny: You look unhappy. 1 Lana: I watched a movie in the morning. Jenny: 2 ] Lana: No. The movie was great. It was the audience (观众)..Some people were late for the movie, some took phone calls during the movie, some made noise while eating snacks and some talked loudly. 3 Jenny: That's too bad! People should obey certain rules while watching a movie. Lana: Yes. The first thing is to keep the theater quiet. We should sit down before the movie begins. 4 We should eat snacks quietly. And we should talk as little as possible. Jenny: 5 And we should take away our rubbish when we leave. Lana: I hope everyone should do these things so that we can enjoy the movie better. ~ Jenny: Me too. A. I was annoyed all the time. B. Who did you go to the movie with C. Yes, you are right … D. How wonderful the movie was! E. What's wrong with you F. We should turn off our mobile phones. G. So the movie was boring, wasn't it 》 2、Three Apples changed the world. The first one seduced(诱惑)Eve. The second one awakened Newton. 71 Here are some famous words from Steve Jobs to share. On character I’m the only person I know that’s lost a quarter of a billion dollars in one year. 72 On good design That’s been one of my mottos－focus and simplicity. Simple can be harder than complex；You have to work hard to get your thinking clean to make it simple. But it’s worth it in the end because once you get there，you can move mountains. 【 On his outlook 73 Going to bed at night saying we’ve done something wonderful，that’s what matters to me. On your working life Your work is going to fill a large part of your life，and the only way to be truly satisfied is to do what you believe is great work. 74 If you haven’t found it yet，keep looking. Don’t settle. On the importance of death -

人教版初三化学生活中常见的盐培优综合训练题含答案解析

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2017陕西中考数学第17题--尺规作图专题练习复习

图（1） 图（2） 2015中考数学--尺规作图（复习） 班别： 姓名： 学号： 一、理解“尺规作图”的含义 1.在几何中，我们把只限定用直尺（无刻度）和圆规来画图的方法，称为尺规作图．其中直尺只能用来作直线、线段、射线或延长线段；圆规用来作圆和圆弧．由此可知，尺规作图与一般的画图不同，一般画图可以动用一切画图工具，包括三角尺、量角器等，在操作过程中可以度量，但尺规作图在操作过程中是不允许度量成分的． 2.基本作图：（1）用尺规作一条线段等于已知线段；（2）用尺规作一个角等于已知角. 利用这两个基本作图，可以作两条线段或两个角的和或差. 二、基本作图 最基本,最常用的尺规作图,通常称基本作图。一些复杂的尺规作图都是由基本作图组成的。 五种基本作图： 1、作一条线段等于已知线段； 2、作一个角等于已知角； 3、作已知线段的垂直平分线； 4、作已知角的角平分线； 5、过一点作已知直线的垂线； 1.作一条线段等于已知线段。 已知：如图，线段a . 求作：线段AB ，使AB = a . 作法： （1） 作射线AP ； （2） 在射线AP 上截取AB=a . 则线段AB 就是所求作的图形。 2. 作一个角等于已知角。 求作一个角等于已知角∠MON （如图1）． 已知：如图，∠MON . 求作：∠COD ，使∠COD =∠MON . 作法：（1）作射线11M O ； （2）在图（1）上，以O 为圆心，任意长为半径作弧，交OM 于点A ，交ON 于点B ； （3）以1O 为圆心，OA 的长为半径作弧，交 11M O 于点C ； （ 4）以C 为圆心，以AB 的长为半径作弧，交前弧于点D ；（5）过点D 作射线D O 1． 则∠D CO 1就是所要求作的角．

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初中数学圆随堂练习17 一、选择题（共5小题；共25分） 1. 已知的半径为，点在上，则的长为 2. 如图，是的直径，，是上两点，，则等于 A. B. C. D. 3. 如图中正方形、矩形、圆的面积相等，则周长的 大小关系是 A. B. C. D. 4. 如果一个圆锥的主视图是正三角形，则其侧面展开图的圆心角为 A. B. C. D. 5. 下列关于圆的切线的说法正确的是 A. 垂直于圆的半径的直线是圆的切线 B. 与圆只有一个公共点的射线是圆的切线 C. 经过半径的一端且垂直于半径的直线是圆的切线 D. 如果圆心到一条直线的距离等于半径长，那么这条直线是圆的切线 二、填空题（共4小题；共20分） 6. 切线的性质： 圆的切线于过切点的半径． 几何语言： ， ．

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初中数学圆随堂练习46 一、选择题（共5小题；共25分） 1. 的半径为，一点到圆心的距离，则点 A. 在内或圆周上 B. 在外 C. 在圆周上 D. 在外或圆周上 2. 如图，是的中点，与相等的角的个数是 A. B. C. D. 3. 如图中正方形、矩形、圆的面积相等，则周长的 大小关系是 A. B. C. D. 4. 如图，是圆锥的母线，为底面直径，已知，圆锥的侧面积为， 则的余弦值为 A. B. C. D. 5. 如图，的半径为，点是外的一点，，点是上的一个动点，连接 ，直线垂直平分，当直线与相切时，的长度为

A. C. 二、填空题（共4小题；共20分） 6. 如图，，是的切线，，为切点．点，在上．若，则 ． 7. 如图，在的网格图中（每个小正方形的边长均为个单位），的半径为，的 半径为，要使与静止的相切，那么由图示位置需向右平移个单位． 8. 如图，网格的小正方形的边长均为，小正方形的顶点叫做格点．的三个顶点都在格点 上，那么的外接圆半径是． 9. 已知中，，，，与斜边有公共点，那么 的半径长的取值范围是． 三、解答题（共4小题；共52分） 10. 一个圆形零件的部分碎片如图所示．请你利用尺规作图找到圆心．（要求：不写作法，保留 作图痕迹） 11. 如图，画出的角平分线，，．

12. 如图，正方形中，是边上一点，以为圆心，为半径的半圆与以为圆 心，为半径的圆弧外切，求的值． 13. 如图，已知的半径是的直径，是上一点，过点作的垂线， 分别交和于，和，四点，，．求线段的长．

答案 第一部分 1. D 2. B 3. D 【解析】【分析】设相同的面积为未知数，进而判断出相应的周长，比较即可． 【解析】解：设面积是． 则正方形的边长是，则周长； 长方形的一边长，则另一边长为，则周长， ， ， 即； ，π， ， ． 故选：． 【点评】考查圆的认识的相关知识；应用这个知识点进行解答是解决本题的难点．4. B 【解析】， ， 底面周长， 侧面积为， ， ， ． 5. B 【解析】如图所示．连接，（为切点），过点作， 设的长为， 在中，，

初三数学圆的专项培优练习题(含答案)

初三数学圆的专项培优练习题(含答案) -CAL-FENGHAI-(2020YEAR-YICAI)_JINGBIAN

初三数学圆的专项培优练习题（含答案） 1．如图1，已知AB是⊙O的直径，AD切⊙O于点A，点C是EB的中点，则下列结论不成立的 是（） A．OC∥AE B．EC=BC C．∠DAE=∠ABE D．AC⊥OE 图一图二图三2．如图2，以等边三角形ABC的BC边为直径画半圆，分别交AB、AC于点E、D，DF是圆的切线，过点F作BC的垂线交BC于点G．若AF的长为2，则FG的长为（） A．4 B．33C．6 D．23 3．四个命题： ①三角形的一条中线能将三角形分成面积相等的两部分； ②有两边和其中一边的对角对应相等的两个三角形全等； ③点P（1,2）关于原点的对称点坐标为（－1，－2）； ④两圆的半径分别是3和4，圆心距为d，若两圆有公共点，则1

A．19° B．38° C．52° D．76° 图四图五 6．如图五，AB为⊙O的直径，弦CD⊥AB于点E，若CD=6，且AE：BE =1：3，则AB= ．7．已知AB是⊙O的直径，AD⊥l于点D． （1）如图①，当直线l与⊙O相切于点C时，若∠DAC=30°，求∠BAC的大小； （2）如图②，当直线l与⊙O相交于点E、F时，若∠DAE=18°，求∠BAF的大小． 8．如图，AB为的直径，点C在⊙O上，点P是直径AB上的一点（不与A，B重合），过点P作AB的垂线交BC的延长线于点Q。在线段PQ上取一点D，使DQ=DC，连接DC，试判断CD与⊙O的位置关系，并说明理由。

初中数学圆随堂练习58

初中数学圆随堂练习58 一、选择题（共5小题；共25分） 1. 的半径为，一点到圆心的距离，则点 A. 在内或圆周上 B. 在外 C. 在圆周上 D. 在外或圆周上 2. 如图所示，把一个量角器放置在的上面，根据量角器的读数可得的度数是 A. B. C. D. 3. 如图中正方形、矩形、圆的面积相等，则周长的 大小关系是 A. B. C. D. 4. 如图，如果从半径为的圆形纸片剪去圆周的一个扇形，将留下的扇形围成一个圆锥（接 缝处不重叠），那么这个圆锥的高为． 5. 在直角平面坐标系中，的半径为，则直线与的位置关系是 A. 相离 B. 相交 C. 相切 D. 以上三种情况都有可能 二、填空题（共4小题；共20分） 6. 如图，是的直径，与相切于点，，．

7. 如图，在的网格图中（每个小正方形的边长均为个单位），的半径为，的 半径为，要使与静止的相切，那么由图示位置需向右平移个单位． 8. 两直角边长分别为和的直角三角形的外接圆直径是． 9. 已知中，，，，与斜边有公共点，那么 的半径长的取值范围是． 三、解答题（共4小题；共52分） 10. 如图，分别作出锐角三角形、直角三角形、钝角三角形的外接圆，它们外心的位置有什么特点? 11. 如图所示，已知及线段，求作点，使点到，的距离相等，且 ． 12. 如图，已知与交于，两点，点在上，是的直径，交 于，是的弦，交于．若，，，求的半径．

13. 如图，已知矩形的边经过圆心，点，分别是边，与的交点， 厘米，厘米，厘米，求的直径长．

答案 第一部分 1. D 2. D 3. D 【解析】【分析】设相同的面积为未知数，进而判断出相应的周长，比较即可． 【解析】解：设面积是． 则正方形的边长是，则周长； 长方形的一边长，则另一边长为，则周长， ， ， 即； ，π， ， ． 故选：． 【点评】考查圆的认识的相关知识；应用这个知识点进行解答是解决本题的难点． 4. B 5. C 第二部分 6. 7. ，，或 8. 【解析】由勾股定理得，直角三角形的斜边长， 由圆周角定理得，这个直角三角形的外接圆直径为． 第三部分 10. 如图：

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