非谓语动词作主语的形式 非谓语动词作主语和表语的比较

非谓语动词作主语和表语的比较  

一、不定式和动名词作主语与表语的比较表示具体的、一次性的或将来的动作用不定式；表示一般的、泛指的或习惯性的行为用动名词。
如：◎ ________ is a good form of exercise for both young and old. (全国卷)
A. The walk                       
B. Walking
C. To walk                         
D. Walk
【分析】答案选B。a good form暗示泛指一般性行为，用动名词作主语。说明：①有时这种区别并不很严格。但要注意：主语和表语要用同一种形式；平行结构中要用同一种形式。

如：◎ —What do you think made Mary so upset? — ________ her new bike. (上海卷)
A. As she lost                     
B. Lost
C. Losing                           
D. Because of losing
【分析】答案选C。去掉问句中的插入语do you think，便知要回答的是主语what。选项中只有动名词Losing可作主语，全句应为：Losing her new bike made Mary so upset. 此处的动名词短语表示的是具体的一回事。

◎ The purpose of new technologies is to make life easier, ________ it more difficult. (全国卷)
A. not make                        
B. not to make
C. not making                     
D. do not make
【分析】答案选B。前面用的是不定式作表语，与之并列的也应用不定式。

◎ Fishing is his favorite hobby, and ________. (上海卷)
A. he’d like to collect coins as well          
B. he feels like collecting coins, too
C. to collect coins is also his hobby         
D. collecting coins also gives him great pleasure
【分析】答案选D。and连接两个并列句，前一分句用-ing形式作主语，与之并列的后一分句也应用-ing形式作主语。 ②通常只用动名词用主语的4种情况：在疑问句中；在It is no good / use…, It is useless…, There is no…等句型中；在某些动词的被动式前；在No smoking!之类的布告语中。如：1. Is doing morning exercises good for your health? 做早操对身体有益处吗？2. It’s useless arguing with them. 和他们讨论是没用的。3. Walking on the grass is forbidden. 禁止在这草地上行走。 ③通常只用不定式作主语的4种情况：在It is necessary / important / …(for sb. ) to do sth. 句型中；It is kind / foolish / …(of sb. ) to do sth. 句型中；在It takes sb. time to do sth. 型句中；主语被否定时。如：1. It is necessary for us to master a foreign language. 我们有必要掌握一门外语。2. It is very kind of you to help us. 你帮助我们真是太好了。3. It took me o hours to finish the work. 我完成那项工作用了两小时。4. Not to have hope is the poorest of all conditions. 绝望是最糟糕的事。
　　
二、不定式、动名词、分词作表语的比较不定式和动名词作表语相当于名词作表语，表示主语的内容，主语和表语可以对调；分词作表语相当于形容词作表语，主语和表语不可对调；现在分词作表语表示主语所具有的性质特征，过去分词作表语表示主语所处的状态。如不定式和动名词作表语相当于名词作表语，表示主语的内容，主语和表语可以对调；分词1. My job is teaching / to teach English. (作表语的teaching / to teach English是my job的具体内容，可说成Teaching / To teach English is my job. )3. The movie is exciting. (exciting是主语the movie是性质特征。)4. They are excited at the news. (excited表示they现在所处的状态上海卷

【分析】答案选C。表示“就坐”的seat是及物动词，若后面没有sb. 或oneself作其宾语，就一定是seated，所以选C；此处的过去分词seated表示状态，remain=continue to be依然，保持。注：在seem, appear, prove(结果是、后来表明), remain(尚须)等连系动词后，可用不定式作表语，但不用-ing形式作表语。

如：Having a trip abroad is certainly good for the old couple, but it remains　 ________ whether they will enjoy it. (全国卷)
A. to see                                    
B. to be seen
C. seeing                                    
D. seen
【分析】答案选B。remain作“尚须“解，后面通常接不定式；it(形式主语，指whether they will enjoy it)与see是被动关系，所以用不定式的被动式。