问题 问答题 简答题

说明调节阀手把(汽门)的构造和怎样调整?

答案

参考答案:

调节阀由齿形板、齿形滑块、导架、手把,活动连杆,曲拐手柄,螺栓、弹簧、手把安装座,杠杆支点轴组成,当手把向前推至与止棒相碰时,如调节阀尚未关闭,可放松连杆上的防缓螺母,旋动拉杆,使其缩短而得到调整。

阅读理解

After a day of work and play, the body needs to rest. Sleep is necessary for good health. During this time, the body recovers from the activities of the previous day. The rest that you get while sleeping enables your body to prepare itself for the next day.

There are four levels of sleep, each being a little deeper than the one before. As you sleep, your muscles relax little by little. Your heart beats more slowly, and your brain slows down. After you reach the fourth level, your body shifts back and forth from one level of sleep to the other.

Although your mind slows down, from time to time you will dream. Scientists who study sleep state that when dreaming occurs your eyeballs begin to move quickly (although your eyelids are closed). This stage of sleep is called REM, which stands for rapid eye movement.

If you have trouble falling asleep, some people recommend breathing very slowly and very deeply. Other people believe that drinking warm milk will help make you drowsy. There is also an old suggestion that counting sheep will put you to sleep.

小题1:A good title for this passage is _______.

A.Sleep.

B.Good Health

C.Dreams

D.Work and Rest小题2:The word “drowsy” in the last paragraph means_______.

A.sick

B.asleep

C.a little sleepy

D.noisy小题3:This passage suggests that not getting enough sleep might make you _______.

A.dream more

B.have poor health

C.nervous

D.breathe quickly小题4:During REM ________.

A.your eyes move quickly

B.you dream

C.you are restless

D.both A and B小题5:The average number of hours of sleep that an adult needs is_________.

A.approximately(大约) six hours.

B.around ten hours.

C.about eight hours

D.not stated here.

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