不定式的时态和语态是常考点。

　　He seemed to be waiting for someone．(进行性)

　　He felt ashamed to have done such a thing．(表在谓语词前已发生)

　　The book is said to have been translated into Chinese．(表在谓语前已被做)

　　He asked not to be sent home． (否定，被动)

　　动名词

　　I apologized for not having kept my promise．(动名词的完成体，表在谓语所表动作前已发生)

　　He was lucky to escape being killed in the car accident．(动名词的被动式)

　　现在分词

　　NMET2001, 35

　　_________such heavy pollution already, it may now be too late to clean up the river．

　　A．Having suffered 　B．Suffering 　C．To suffer 　D．Suffered

　　答案为A，现在分词的完成被动形式，表已发生在主句前的动作。

　　The building being repaired is our library．(被动形式，正在被)

　　Having been given such a good chance, how could she give it up ?(现在分词的完成被动形式，常代之以过去分词。

　　过去分词

　　只有一种形式，表完成或被动概念。

非谓语动词作句子成分

　　独立主格结构

　　有时，作状语部分的动词和句子主语没有合理联系，但为了表达的简洁性，仍然采用短语形式来作状语，但状语本身自带主语。

　　 Weather permitting, we’ll go to the seaside．(=If weather permits)

　　 There being no buses, we had to walk home on foot．(=As there were no buses)

　　动名词的复合结构

　　构成形式为：名词’s (或物主代词) +动名词---作主语

　　名词(或名词)/ 物主代词(或人称代词的宾格形式)+动名词---作宾语

　　 His coming made us happy．

　　I’m surprised at his(him)saying that

独立主格结构

　　有时，作状语部分的动词和句子主语没有合理联系，但为了表达的简洁性，仍然采用短语形式来作状语，但状语本身自带主语。

　　 Weather permitting, we’ll go to the seaside．(=If weather permits)

　　 There being no buses, we had to walk home on foot．(=As there were no buses)

　　动名词的复合结构

　　构成形式为：名词’s (或物主代词) +动名词---作主语

　　名词(或名词)/ 物主代词(或人称代词的宾格形式)+动名词---作宾语

　　 His coming made us happy．

　　I’m surprised at his(him)saying that．