①作原因状语。相当于as, since, because引导的原因状语从句。 例 Being tired, I stopped to have a rest. (=Because I was tired, I stopped to have a rest.)
②作条件状语。相当于if引导的条件状语从句。 例 Turning to the left, you will find the school. (=If you turn to the left, you will find the school.)
③作让步状语。相当于though, although, even if 引导的让步状语从句。例 Knowing where I live, he never comes to see me. (=Though he knows where I live, he never comes to see me.)
④作结果状语。相当于so that 引导的结果状语从句。例 He turned off the lamp, seeing nothing. (=He turned off the lamp so that he saw nothing.) 现在分词短语作结果状语时,表示一种自然而然的结果,通常放在句末,与句子其他部分用逗号隔开;不定式作结果状语时往往表示一个不好的或出乎意料的结果。
⑤作方式状语或伴随状语,此时现在分词短语不能转化为状语从句,但可转化为并列分句。The condition normally occurs in elderly people and is irreparable, resulting in permanent loss of vision.
⑥作时间状语,相当于when,while引导的时间状语从句。例 Hearing the news, they immediately set off for Shanghai. (=When they heard the news, they immediately set off for Shanghai.)
①作时间状语。可转换为when, while引导的时间状语从句。例 Asked what had happened, he told us about it.→When he was asked what had happened, he told us about it.
②作条件状语。可转换为if引导的条件状语从句。例 Given more time, I'll catch up with you.→If I am given more time, I'll catch up with you.
③作原因状语。可转换为because, as等引导的原因状语从句。例 Encouraged by the progress he has made, he works harder.→As he is encouraged by the progress he has made, he works harder.
④作让步状语。可转换为though, although, even if等引导的让步状语从句。例 Left at home, John didn't feel afraid at all.→Although he was left at home, John didn't feel afraid at all.
⑤作方式状语或伴随状语。一般不能转换为状语从句,但可转换为并列分句。例 Dressed in white, she suddenly appeared.→She was dressed in white and suddenly appeared.
表语
不定式作表语:不定式在系动词后作表语,可表示主语的内容、将来的动作、命令、建议、事态发展的结果等。 例1 His job is to write reports for the newspaper. 例2 The problems remain to be unsettled.
现在分词作表语:①相当于名词,用于解释主语的内容,表语和主语常常可以互换位置。②相当于形容词,用于说明主语的特征,主语和表语不可以互换位置。例1 My favorite sport is swimming. (动词-ing作表语) 例2 The result is very disappointing. (动词-ing作表语)
过去分词作表语:①位于系动词之后,多用于表示主语的状态或状况,所体现的是形容词的特性。例 I am pleased with the result of the experiment. ②强调主语所处的状态;动词的被动语态则表示主语是动作的承受者,强调动作。例1 The cup is broken. (强调杯子的状态) 例2 The cup was broken by Jim. (强调"打破"这一动作)
补语
to do
①带to的不定式作补语。动词allow, order, permit, tell, want, wish, forbid, advise, persuade, warn等之后跟带to的不定式作补语,形式为动词+宾语+宾补(不定式)或动词(被动)+主补(不定式)。例 He didn't allow us to smoke in his room.
②不带to的不定式作补语。使役动词(make, have, let等)及感官动词(see, watch, observe, hear, notice等)后作宾补的不定式不带to。但使役动词和感官动词用于被动语态(let一般不用于被动语态)时,作主补的不定式一定要加上to。例1 He made a face and made everybody laugh. 例2 He was seen to go upstairs.
doing
①感觉、感官类动词:see, notice, watch, look at, hear, listen to, find, feel, smell等。例1 He heard the wind blowing outside. 例2 I felt my heart beating faster.
②使役动词:keep, get, leave, set, have等。例1 I am sorry to have kept you waiting for so long. 例2 Her joke set us laughing.
done
①位于feel, find, hear, notice, see, smell, observe等感官动词后作补语。例1 He didn't notice his wallet stolen. 例2 I was sleeping when I heard my name called.
②位于get, have, make, keep, leave等使役动词后作补语。例 They are going to have the house painted white.
不定式作主语:不定式作主语时谓语动词用单数;若不定式太长,则用it作形式主语而将不定式后置。例1 To say is one thing; to do is another. 例2 To talk with him is a great pleasure.→It is a great pleasure to talk with him.
动词的现在分词形式作主语:①意义:多表示一般性的、抽象的动作或状态 ②谓语动词的数:通常用单数形式 ③位置:位于句首;也可位于句末,此时常用 it作形式主语 ④动词-ing的逻辑主语:形容词性物主代词、名词所有格 例1 Living in the city brings him lots of job chances. 例2 Jack's suddenly disappearing made them worried.
宾语
不定式作宾语:下列动词后只接不定式作宾语而不接动名词作宾语agree (同意), intend/plan (打算,计划), demand (要求), promise (答应), help(帮忙), prepare (准备), decide (决定), refuse (拒绝), choose (选择,决定), wish/hope(想要), want(想), expect (期望), fail(未能), pretend (假装), manage (设法完成), determine(决心), beg (恳求), arrange(安排), threaten(威胁), claim(声称), hesitate(顾虑), happen(碰巧)等。例1 They managed to finish the work on time. 例2 Don't pretend to know what you don't know.
①下列动词后接动词-ing作宾语而不接不定式作宾语:admit(承认), avoid, consider(考虑), escape(避开), imagine, mind, miss, practise, suggest(建议), enjoy等。例1 I often practise listening and speaking. 例2 Do you mind passing me that dictionary?
②下列短语动词后接动词-ing作宾语:can't help(不禁), feel like, give up, put off, object to, look forward to等。例 I object to being scolded for the matter. 巧记后接动词-ing作宾语的(短语)动词: 建议 考虑 坚持 练(suggest, advise, consider, insist on, practise) 允许 想象 弃 冒险(permit, allow, imagine, give up, risk) 阻止 抵抗 否 避开(prevent, resist, deny, escape) 不禁 介意 保持 完(can't help, mind, keep, finish) 承认 错过 心喜欢(admit, miss, enjoy)