机床的静态精度也可以是在机床低速下检测的精度。( )

题型:判断题

问题:

机床的静态精度也可以是在机床低速下检测的精度。( )

考点:组合机床操作工高级组合机床操作工高级
题型:判断题

阅读理解。

                                                         The World's Water Shortage

     The world is not only hungry, but it is also thirsty for water. This may seem strange to you, since nearly

  70 percent (百分比) of the earth's surface is covered with water. But about 97 percent of this huge

  amount is sea water, or salt water. Man can only drink and use the other 3 percent-the fresh water from

  rivers, lakes, underground, and other sources (资源). And we cannot even use all of that, because some

  of it is in the form of icebergs and glaciers(冰川). Even worse, some of it has been polluted.

     However, as things stand today, this small amount of fresh water is still enough for us. But our need for

  water is increasing (增加) rapidly-almost day by day. Only if we take steps to deal with this problem

 now can we avoid (避免) a severe (严重的) worldwide water shortage later on.

     We all have to learn how to stop wasting our valuable water. One of the first steps is to develop ways

 of  reusing it.

     Today in most large cities, water is used only once and then sent out into a sewer system (下水道).

 From there it returns to the sea or runs into underground storage tanks. But it is possible to pipe used

 water to a purifying (净化) plant. There it can be treated with chemicals so that it can be used again, just

  as if it were fresh from a spring.

     But even if every large city purified and reused its water, we still would not have enough. All we'd have

  to do to make use of the vast reserves (贮备) of sea water in the world is to remove the salt.

     If we take these steps we'll be in no danger of drying up.         

1. The world is thirsty for water because we can only use _____ percent of the water covering the surface

   of the earth. 

    A. 3

    B. more than 3        

    C. less than 3    

    D. 97

2. Which of the following statements is Not true? 

    A. As things remain unchanging, this small amount of fresh water is still enough for us.

    B. Our need for water is becoming larger and larger.

    C. There will be no water shortage in the future.

    D. We should take steps to deal with the water shortage problem.    

3. To reuse water, we should _____ .

    A. treat it with chemicals

    B. use it only once

    C. send it out into a sewer system

    D. make it flow into underground tanks 

4. In order to have enough water, we should also make use of _____ .

    A. icebergs and glaciers

    B. sea water

    C. rivers and lake

    D. underground water 

5. In the passage, the writer tells us _____ .

    A. to make enough water

    B. to pay more attention to the water shortage problem

    C. to pipe used water to a purifying plant

    D. to reuse the water

题型:判断题

以人为本,关注学生的学习与需求是当前基础教育课程改革的重要理念之一,早在文艺复兴时期人们就开始倡导个性,崇尚人性。

请回答:

(1)文艺复兴开始于哪个国家?它的本质是什么?举出文艺复兴时期的重要代表人物。

(2)请你选择文艺复兴时期的任何一项作品,来谈谈它是如何体现人文主义思想的。

(3)文艺复兴运动有什么意义?

题型:判断题

从所给的四个选项中,选择最合适的一个填入问号处,使之呈现一定的规律性()

A.选项A

B.选项B

C.选项C

D.选项D

题型:判断题

预叠加电码化是列车进入()时,不仅本轨道区段且相邻轨道电路区段也实施的电码化。

题型:判断题

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