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问题 选择题

下列说法中正确是（　　）

A．沿电场线的指向，电场强度一定越来越小

B．沿电场线的指向，电势一定越来越低

C．沿电场线方向移动电荷，电势能逐渐减小

D．只在电场力作用下，电荷一定从电势高处向电势低处移动

答案

A、电场线越密，场强越大，沿电场线的指向，电场强度不一定越来越小，故A错误

B、沿电场线的方向电势降低，故B正确

C、沿电场线方向移动正电荷，电势能逐渐减小，沿电场线方向移动负电荷，电势能逐渐增大，故C错误

D、只在电场力作用下，负电荷可以从电势低处向电势低高处移动，故D错误

故选B．

单项选择题

A group of frogs were traveling through the forests, but unluckily two of them fell into a hole. The other frogs tried to help them. When they saw how (1) the hole was, they cried to the two frogs that they could not be saved. The two frogs didn’t (2) and tried their best to jump up out of the hole. The other frogs (3) saying that they were sure to die. (4) , one of the two frogs, who heard what the other frogs were saying, (5) Then he fell down and died.
The other frog, however, (6) to jump as hard as he could, and at last made it out. When he (7) , the other frogs asked, "Didn’t you hear us" The frog, who had a poor (8) , explained, "I thought you were encouraging me all the time. "
The story teaches us a (9) : There is power (力量) of life and death in the tongue. An (10) word to those who are down can help them out while a discouraging word can kill them.

Ⅰ. 完形填空

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阅读下列短文，从每小题所给的A、B、C、D四个选项中选出一个最佳选项。

A．happened

B．continued

C．planned

D．wanted
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名词解释

英式拍卖
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