【练习】

1. Taking this medicine, if _____(continue) , will of course do good to his health. （填空练习）

答案：continued

解析：if continued 是“if taking this medicine is continued”的省略形式。

2. In the face of the big fire in October in California, many people in the fire-stricken areas moved out  _____(escape ; burn)   （填空练习）

答案： to escape being burned不定式作目的状语。

解析： escape 意为“逃脱”，不接不定式，而常接-ing形式作宾语。只能接-ing形式作宾语的动词还有:mind， admit，avoid，appreciate，consider(考虑)， delay， imagine，miss，practice等。

3. O'Neal works hard.He is often seen ＿＿＿heavily before his teammates start.

A.sweated   B.to be sweated   C.sweating   D.being sweated

答案：C

解析：分词在句中作主语补足语。因sweat这一动作是he所发出，所以为主动。

4. I remained _______ long after I had been told the story.

A. puzzling   B. puzzled     C. being puzzled    D. to be puzzled

答案： B

解析：  puzzled 表主语感到迷惑不解的，puzzling 表令人迷惑不解的，beingpuzzled强调正在进行的被动动作，to be puzzled表在主句谓语之后发生。

5. I can hardly imagine Peter_______ across the Atlantic Ocean in 15 days.

A.sail   B.to sail   C.sailing   D.to have sailed

答案： C

解析： Peter为逻辑主语，与sailing构成复合结构，作imagine的宾语。

6. I _____(drive) along the quiet road at forty miles an hour, and then an old man suddenly started to cross the road in front of me.  （填空练习）

答案：was driving

解析： 因句中有连词and，所以and 之前必须是一个并列关系的分句。

【小知识】复合结构动词不定式

复合结构不定式：由for + 名词（或代词宾格）+ 动词不定式即构成复合结构的动词不定式。

其中for本身无意义。for后面的名词或代词是不定式的逻辑主语，这种不定式在句中可作主语、表语、宾语、定语或状语，如：It is very important for us to get everything ready for the harvest.

当作表语用的形容词表示不定式的逻辑主语的性质或特征时，就用介词of而不用for引出不定式的逻辑主语，这些形容词一般有good, nice, kind, wise, silly, stupid, foolish, right, wrong, careless, impolite等，如：It is very kind of you to help him every day.