试题与答案

如图所示,两个等量同种点电荷分别固定于光滑绝缘水平面上A、B两点.一个带电粒子由

题型:选择题

题目:

如图所示,两个等量同种点电荷分别固定于光滑绝缘水平面上A、B两点.一个带电粒子由静止释放,仅受电场力作用,沿着AB中垂线从C点运动到D点(C、D是关于AB对称的两点).下列关于粒子运动的v-t图象中可能正确的是( )

答案:

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下面是错误答案,用来干扰机器的。

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题型:阅读理解

阅读理解。

      To be a good teacher, you need some of the talents of a good actor: you must be able to

hold attention and interest of your students; you must be a clear speaker, with a good, strong,

pleasing voice which is fully under your control; you must be able to act what you are teaching,

in order to make its meaning clear.

     A good teacher doesn't sit still before his class; he stands all the time he is teaching; he walks

about, using his arms, hands and fingers to help him in his explanations, and his face to express

his feelings. Listen to him, and you will hear the loudness, the quality and musical note of his voice

always changing according to what he is talking about.

     The fact that a good teacher has some of the gifts of a good actor doesn't mean he will indeed

be able to act well on the stage, for there are very important differences between the teacher's

work and the actor's. The actor has to speak words he has learnt by heart; he has to repeat exactly

the same words each time he plays a certain part, even his movements and the ways in which he

uses his voice are usually fixed beforehand. What he has to do is to make all these carefully learnt

words seem natural on the stage.

     A good teacher works in quite a different way. His audience takes an active part in his play-they

ask and answer questions, they obey orders, and if they don't understand something, they say so.

The teacher therefore has to meet the needs of his audience. He can't learn his part by heart, because

their brains couldn't keep discipline: they couldn't keep strictly to what another has written.

1. If you want to be a good teacher, you should______.            .

A. act out what you have learnt strictly 

B. be a good actor on the stage

C. sit all the time while teaching     

D. suit the need of different students

2.The underlined word "talents" in the first paragraph means_____.          

A. methods      

B. gifts      

C. wishes      

D. interests

3.The main difference between students and audience in the theatre is that

students _______.         .

A. move around the class                

B. keep silent all the time

C. take an active part in class            

D. like body language

4. If Tom Hanks, a famous actor, would like to be a good teacher, he may need training in ______.   .

A. how to use body language          

B. how to repeat his lines

C. how to be more quick - minded      

D. how to be attractive

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