1.He acts as if （_____ ________) a fool．

2.She left the room hurriedly as if （_______ ________）angry.

3.she looked about as if (_______ ___________) in search of sth.

4.He moved his lips as if (_____ ______) to say sth.

5.From time to time Tom turned round as if (_______ _____) searching someone.

6.The football players is rolling on the ground as if (_______ ________)hurt badly in leg.

as if 还可用于省略句中，当as if 从句的主语和主句的主语一致时，并且从句的谓语动词是连系动词，可以省略______+_________，只留下_______、________、______________、___________、___________、____________.

　　as if 引导从句的语气

1.陈述句语气（陈述的是事实或是可能发生的事情）

It sounds as if it is raining.

听起来像是下雨

2.虚拟语气（说话者陈述的是不存在或不真实的事情时候

(1)如果从句表示与现在事实相反，谓语动词用一般过去时。

如：You look as if you didn't care．

(2)从句表示与过去事实相反，谓语动词用"had＋过去分词"。

如：He talked about Rome as if he had been there before．

(3)从句表示与将来事实相反，谓语动词用"would／could／might＋动词原形"。

如：He opened his mouth as if he would say something．

【即时巩固】根据汉语句子完成英语句子（完全句和省略句）

(1)汤姆举起手来好像要说什么。

　　Tom raised his hands as if .

(2)他躺在那儿好长时间一动不动，好像死了。

　　He lay still for a long while as if .

　　From time to time Jack turned around as if someone.

2. 【教材原句】No. I must have forgotten to tell you. 不。我一定是忘记告诉你们了。

You musts have visited the Shanghai World Expo,__________ ________?

你准是参观过上海世博会，是不是？

She must have attended the meeting yesterday evening,________ _______?

她昨晚一定已经参加过那个会议，是不是？

【归纳总结】：陈述部分是must+ have done 表示对已经发生的事情的猜测，附加疑问句应依具体情况分别用法不同。如果有明确表示过去的时间状语，就用_______,否则用_____/_____.

You ______ ______ _______ a whole night playing computer games.

你本不因该浪费一个晚上的时间玩电脑游戏。

You ______ _____ ______ ______ ,but why didn't you ? 你本该来，怎么没有来呢？

I can't find my key .It ______ _____ ______ ______ by someone by mistake .我找不到钥匙。或许被人拿错了。

You're late again. You ______ ______ ______ earlier.你又迟到了，你本可以早点来的。

The meeting has been called off. You _______ ______ _______.回忆取消了，你没有必要来。

【归纳总结】：should have done 表示________________ could have done 表示____________

May/might have done 表示_______________ needn't have done 表示__________