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问题 选择题

根据牛顿第一定律可知（　　）

A．物体若不受外力的作用，一定处于静止状态

B．物体的运动是依靠力来维持的

C．运动的物体若去掉外力作用，物体一定慢慢停下来

D．物体运动状态改变时，一定受到外力的作用

答案

A、若物体在不受任何外力时，运动的物体将永远做匀速直线运动，所以该选项错误；

B、若物体在不受任何外力时，运动的物体将永远做匀速直线运动，不依靠力来维持，故该选项错误；

C、运动的物体若去掉外力作用，物体将永远做匀速直线运动，只有受到阻力才会慢慢停下来，故该选项错误；

D、力是改变物体运动状态的原因，即只要物体的运动状态发生改变，其一定是由于受到力的作用，故该选项正确；

故选D．

填空题


In the following passage, there are 20 blanks representing the words that are missing from the context. You are to put back in each of the blanks the missing worD．The time for this section is 20 minutes.
Many things about language are a mystery, and many will always remain so. But some things we do know.
First, we know that all human beings have a language of some sort. (1) is no race of men anywhere on earth so backward that it has (2) language, no set of speech sounds by which the people communicate with one (3) . Furthermore, in historical times, there has never been a race of men (4) a language.
Second, there is no such thing as a primitive language. There are many people (5) cultures are underdeveloped, who are, as we say, uncivilized, but the (6) they speak are not primitive. In all known languages we can see complexities (7) must have been tens of thousands of years in development.
This has not (8) been well understood; indeed, the direct contrary has often been stateD．Popular ideas (9) the language of the American Indians will illustrate. Many people have supposed that the Indians (10) in a very primitive system of noises. Study has proved this (11) be nonsense. There are, or were, hundreds of American Indian languages, and all of them (12) out to be very complicated and very old．They are certainly (13) from the languages that most of us are familiar with, but they are (14) more primitive that English and Greek.
A third thing we know about language (15) that all languages are perfectly adequate. That is, each one is a perfect (16) of expressing the culture of the people who speak the language.
Finally, we (17) that language changes. It is natural and normal for language to change; the (18) languages which do not change are the dead ones. This is easy to (19) if we look backward in time. Change goes in all aspects of language. (20) features change as do speech sounds, and changes in vocabulary are sometimes very extensive and may occur very rapidly. Vocabulary is the least stable part of any language.

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单项选择题

秦始皇统一中国之后采用的是：（）

A、分封制

B、省、府、县

C、郡县制

D、地方三级制
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