问题 单项选择题

对于算法的每一步,指令必须是可执行的。算法的( )要求算法在有限步骤之后能够达到预期的目的。

A.可行性
B.有穷性
C.正确性
D.确定性

答案

参考答案:A

阅读理解

阅读理解。

     You're rushing to work and a man ahead of you collapses on the sidewalk. Do you stop to help? In a

study of by-standers, it was found that some people avert their gaze and keep on walking rather than stop

and get involved.

     "There is a tendency to decide that no action is needed. " says a psychologist. "The first thoughts that

pop into your mind often keep you from offering help. In order to take action, you have to work against

them. " Here are some common thoughts that might prevent you from helping. 

     ● Why should I be the one? I'm probably not the most competent (有能力的) person in this crowd. You

might think someone older or with more medical knowledge should offer assistance. 

     ● What if he doesn't really need my help? The fear of embarrassment is powerful; no one wants to risk

looking foolish in front of others. 

     ● No one else looks concerned-this must not be a problem. We can follow the people around us, but most

people tend to hold back their emotions in public.

     "If you spot trouble and find yourself explaining inaction, force yourself to stop and evaluate the situation

instead of walking on," says the psychologist. "Then retry to involve other people; you don't have to take on

the entire responsibility of being helpful. Sometimes it's just a matter of turning to the person next to you and

saying, 'It looks like we should do something. ' Or asking someone if an ambulance has been called and, if not,

to call for one. Once you take action, most people will follow you."

1. Which is NOT the common thought that stops you from helping others?

A. I'm not the very person capable of settling the problem.

B. It looks like we should do something.

C. It must not be a problem as no one else is concerned.

D. He doesn't really need my help.

2. According to a study of by-standers, what will some people do when a man ahead falls down on the sidewalk?

A. They will call for help and then walk away.

B. They will stop and offer help.

C. They will turn away their eyes and goon walking.

D. They will laugh at him.

3. We learn from the last paragraph that if we spot trouble, _____.

A. we should call the ambulance as soon as we can

B. we should take on the whole responsibility and do something alone

C. we should stop and evaluate the situation and try to make other people follow

D. we should turn to other people and ask them to take on the responsibility

4. In order to offer others your timely help, you need to _____.

A. ask others for help and call the police

B. get along well with the passers-by who spot the trouble

C. go directly to the police station

D. work against the first thoughts that prevent you offering help

5. The main purpose of the text is to tell readers _____. 

A. to give others a hand

B. to be more competent

C. not to risk looking foolish

D. to stop and evaluate the situation

单项选择题 A1/A2型题