问题 单项选择题

根瘤细菌与豆科植物互相依存,其相互关系为________。

A.种内互助

B.互利共生

C.捕食

D.竞争

答案

参考答案:B

解析:(根瘤细菌能把氮气固定成为含氮养料,而豆科植物为根瘤细菌提供了有机养料,因此它们的关系是互利共生。)

阅读理解

阅读理解。

     A punctual person is in the habit of doing a thing at the proper time and is never late in

keeping an appointment(约会).

     The unpunctual man, on the other hand, never does what he has to do at the proper time.

He is always in a hurry and in the end loses both time and his good name. A lost thing may

be found again, but lost time can never be regained. Time is more valuable than material things.

In fact, time is life itself. The unpunctual man is forever wasting and mismanaging his most

valuable asset(财产)as well as others'. The unpunctual person is always complaining that he

finds no time to answer letters, or return calls or keep appointments promptly. But the man who

really has a great deal to do is very careful of his time and seldom complains of want of it. He

knows that he cannot get through his huge amount of work unless he faithfully keeps every piece

of work when it has to be attended to.

     Failure to be punctual in keeping one's appointments is a sign of disrespect towards others.

If a person is invited to dinner and arrives later than the appointed time, he keeps all the other

guests waiting for him. Usually this will be regarded as a great disrespect to the host and all other

guests present.

     Unpunctuality, moreover, is very harmful when it comes to do one's duty, whether public or

private. Imagine how it would be if those who are put in charge of important tasks failed to be

at their proper places at the appointed time. A man who is known to be habitually unpunctual is

never trusted by his friends or fellow men.

1. According to the passage, the main reason that a person is always unpunctual is that____.

A. he has more work to do than other people

B. he is always in a hurry when he works

C. he doesn't care much about time

D. he always mismanages and wastes his time

2.What does the underlined word mean?_____

A. in time    

B. be late    

C. on time    

D. at times

3. According to the third paragraph, when you are invited to dinner, you should arrive there ____.

A. after other guests have arrived      

B. at the appointed time

C. before all other guests            

D. after the host has got things ready

4. Which of the following statements best describes the harm of unpunctuality?______

A. If you are an unpunctual person, you cannot be in charge of any important task.

B. Unpunctuality may bring about heavy losses for both public and private affairs

C. If your friends know that you are unpunctual, they may not see you again.

D. Unpunctuality may make you miss a lot of appointments and lose friends.

单项选择题