1.当名词被the first ,the last等序数词以及 the only ,形容词最高级修饰时，常用不定式作定语，而不管动作是否已完成．
He is the only person to know the truth.
She is always the first to come and the last to leave.
2.被修饰词是抽象名词时，常用不定式作定语：ability，chance，idea，hope，wish，fact，excuse，promise，attempt，way等。
And the best way to strengthen willpower is to make it into a habit.
The ability to express an idea is as important as the idea itself.
3.主动形式表被动意义的不定式。 主语＋be +adj. +to do
The question is very difficult to answer.
The armchair is comfortable to sit in .
The book is hard to understand.
这类词有：easy,difficult,hard,cheap,expensive,fit,comfortable,heavy,good,important,impossible,dangerous,surprised,astonished,delighted,disappointed等，表示主语特征、性质或说明产生这种情感的原因。
4.独立主格结构作状语
Weather permitting, we are going to visit you tomorrow.
Time permitting （=If time permits） , I shall stay here for another two days．
The test finished, we began our holiday.
Everything done( =After everything was done) , they went home.noise的形容词
Mother being ill in bed （=Because Mother was ill in bed）, he couldn’t go to work.
He came out of the library, a large book under his arm.
feel / hear , listen to / see, watch, notice, observe, look at
感官的动词+宾语+ | do 看见...做了（全过程）... |
doing 看见...正在做... | |
done 看见....被做... | |
I heard her sing an English song.
I heard her singing an English song when I passed her room.
I see him beaten by those bad boys.
6. 4个使役动词 : have，make，let，get+宾语+宾补（非谓语动词）
※ make/let +宾语+ do sth 迫使某人做某事，被动语态为be made to do sth
He made me laugh.
I was made to laugh by him
Let’s go there , shall we ?
※ make /let +宾语+done (动词过去分词)（使某事被做）
He couldn't make himself heard above the noise of the traffic.
Let he clothes washed.
※ have +宾语+do sth
He had her go there.
※ have +宾语+doing sth 表示动作的执行者为宾语,但是动词必须是持续性动词/延续性动词，后面常接一个时间段
He had her standing in the rain for two hours
He had us laughing all through lunch.
※ have +宾语+done 表示叫，让，请别人做某事或遭遇不幸事件
I will have my bike repaired this afternoon
He had his wallet stolen at the railway station.
He had his pocket picked.
※ get +宾语+to do sth
He got his brother to help him.
※ get +宾语+doing sth
He got his bike running very fast
※ get +宾语+done
He got the car started
7.with 的复合结构
“With + 复合结构”又称为“with结构”，在句中表状态或说明背景情况，常做伴随，方式，原因，条件等状语。
※ with + 名词 + to do （不定式动作尚未发生）
With so many people to help us, we are sure to finish it in time．
※ with + 名词 + doing（强调名词是 -ing分词的动作的发出者或某动作，正在进行）
He fell asleep with the lamp burning．他没熄灯就睡着了。
※ With + 名词 + -ed 分词 （强调名词是 -ed分词动作的承受者或动作已经发生）
All the afternoon he worked with the door locked．
8.to作为介词的短语：
9.介词but/ except 表除了，其前有实义动词do时，but / except后的不定式to要省略，否则to则不省.我们用一句话概括就是：前有do后省to
She has no choice but to wait
He could do nothing but wait.
I could do nothing except agree.
10. it作形式主语,构成句型: It’s +n.(adj.)+ for(of) sb. +to do sth.
It is difficult/easy/possible/necessary/...for sb. to do sth.
在某些形容词如clever, good ,nice, kind ,foolish, careless, right, wrong, rude, impolite常加of短语,这是对人做某事的赞扬，责备或感激等。
It is very kind of you to come here.
It is foolish of him to do such a thing.
发布评论