今年英语三级语法指导复习15_大学三级

    非谓语动词是指在句子中不是谓语的动词,主要包括不定式、动名词和分词(现在分词和过去分词),即动词的非谓语形式。非谓语动词除了不能独立作谓语外,可以承担句子的任何成分。
    (一)动词不定式:(to)+do,具有名词、形容词、副词的特征.   
    1.否定式:not + (to) do   
    (1)一般式:不定式的一般式所表示的动作与谓语动词动作同时发生或发生在谓语动词动作之后.   
    例如:
    i’m glad to meet you.   
    the patient asked to be operated on at once.
    (2)进行式:不定式的进行式所表示的动作与谓语动词动作同时发生,
    例如: the boy pretended to be working hard.   he seems to be reading in his room.   
    (3)完成式:不定式的完成式表示的动作发生在谓语动词动作之前,
    例如: i regretted having told a lie.
    i happened to have seen the film.
    2.不定式的句法功能:   
    (1)作主语:   
    to finish the work in ten minutes is very hard. 动词不定式短语作主语时,常用it作形式主语,真正的主语不定式置于句后,例如上面两句可用如下形式:
    it is very hard to finish the work in ten minutes.
    常用句式有:
    1、it+be+名词+to do。
    2、it takes sb.+some time+to do。
    3、it+be+形容词+of sb +to do。
    4、it+be+形容词+for sb.+to do。
    常用careless,clever,good,foolish,honest,kind,lazy,nice,right,silly,stupid,wise,等表示赞扬或批评的形容词,不定式前的sb.可作其逻辑主语。
    (2)作表语:
    her job is to clean the hall.
    (3)作宾语:常与不定式做宾语连用的动词有:want, hope, wish, offer, fail, plan, learn, pretend, refuse, manage, help, agree, promise, prefer, 如果不定式(宾语)后面有宾语补足语,则用it作形式宾语,真正的宾语(不定式)后置,放在宾语补足语后面,例如:marx found it important to study the situation in russia.
    动词不定式也可充当介词宾语,如:i have no choice but to stay here.
    动词不定式前有时可与疑问词连用,如:he gave us some advice on how to learn english.
    (4)作宾语补足语:在复合宾语中,动词不定式可充当宾语补足语,如下动词常跟这种复合宾语:want, wish, ask, tell, order, beg, permit, help, advise, persuade, allow, prepare, cause, force, call on, wait for, invite.
    (5)作定语:动词不定式作定语,放在所修饰的名词或代词后。与所修饰名词有如下关系:
    ①动宾关系:i have a meeting to attend.
    ②说明所修饰名词的内容:we have made a plan to finish the work.   
    ③被修饰名词是不定式逻辑主语:he is the first to get here.   
    (6)作状语:
    ①表目的:he worked day and night to get the money.
    ②表结果(往往是与预期愿望相反的结果):   
    he arrived late only to find the train had gone.他迟到,结果却发现火车已经开走了。
    ③表原因:they were very sad to hear the news.
    ④表程度:it’s too dark for us to see anything.  
    (7)作独立成分:to tell you the truth, i don’t like the way he talked.
    (8)不定式的并列:第二个不定式可省略to。   
    he wished to study medicine and become a doctor.