问题 单项选择题

在清管作业中,由于清管器与管壁密封不严而造成的故障,其处理方法是().

A.确定位置,割管取出清管器

B.无法处理,让清管器停留在管线中

C.增大进气量,提高推球压差

D.前后放空

答案

参考答案:C

阅读理解

阅读理解

     Around the world more and more people are taking part in dangerous sports and activities. Of

course there have always been people who have looked for adventure (冒险) and those who have

climbed the highest mountains or explored unknown parts of the world. Now, however, there are

people who look for a quick pleasure from a dangerous activity, which may only last a few minutes or

even seconds.

     I think bungee jumping is a good example of such an activity. You jump from a high place (maybe a

bridge or a hot-air balloon) 200 meters above the ground with an elastic rope (弹力绳) to your ankles (踝). You fall at up to 150 kilometers an hour until the rope stops you from hitting the ground. It is said

that 2, 000, 000 people around the world have now tried bungee jumping. Most people think that other

activities, such as jumping from the tall buildings and diving into the sea from the top of high rocks are as

dangerous as bungee jumping.

     Why do people take part in such activities? Some scientists think it is because life in modern

societies has become safe and boring. Now life has little excitement. They buy food in shops and there

are doctors and hospitals to look after them if they are ill. The answer for some of these people is to

look for danger in activities as bungee jumping.

1. How many people have now tried bungee jumping?

A. Two hundred.      

B. Two thousand.        

C. Two million.

2. People take part in dangerous sports because              .

A. people want to get excitement from them

B. they have more free time

C. they hate adventure

3. Which of the following descriptions about bungee jumping is right?

A. It's very boring.

B. It's much easier to do.

C. It takes much shorter time to get pleasure.

4. The writer of this passage          .

A. is a lover of dangerous activities himself

B. is against dangerous activities

C. doesn't say whether dangerous activities are good or bad

5. Which of the following pictures shows the right way of bungee jumping?

单项选择题