Unit 5 Meeting your ancestors课时作业

learning about language

第一节 单项选择

1. no modern telecommunications, we would have to wait for weeks to get news from around the world.

　　A. Were there B. Had there been

　　C .If there are D. If there have been

【考点】考察虚拟语气和省略

【答案】A

【解析】本题是一个if条件句的虚拟语气，表示与现在相反，if从句中使用"过去时/were"，主句使用"情态动词+动词原形"；在if被省略的时候，要使用部分倒装。句义：如果没有现代的电信业，要想得到世界各地的消息，我们就不得不等几个星期。故A正确。

2. Children，when by their parents, are allowed to enter the stadium.

A. to be accompanied B. to accompany

C. accompanying D. accompanied

【考点】考察状语从句和省略

【答案】D

【解析】本题考察的是状语从句的省略：当状语从句的主语和主句主语一致且含有be动词的时候，可以把状语从句的主语和be动词一起省略。本题在when的后面省略了they are。因为children和动词allow构成被动关系，所以使用过去分词表示被动。句义：当孩子有父母亲陪伴的时候，他们是被允许进入体育馆的。故D正确。

【试题延伸】本题考察是状语从句的省略，实际上可以把when也省略掉，就变成了非谓语动词中的分词做状语的用法。

3. The experiment shows that proper amounts of exercise, if regularly, can improve our health.

A. being carried out B. carrying out C. carried out D. to carry out

〖答案〗C