1. 動詞不定式的否定式
not to
She decided not to be late again.
2. 動詞不定式的完成式
完成式表示的動作或狀態(tài)發(fā)生在位于動詞表示的動作或狀態(tài)之前。
I am sorry to have kept you waiting.
3. 在It is/was + 形容詞+不定式的復(fù)合結(jié)構(gòu)
若形容詞側(cè)重于評價人物的特性、特征,則構(gòu)成不定式復(fù)合結(jié)構(gòu)的介詞應(yīng)為of。
常用形容詞有:kind, nice, foolish, silly, stupid, rude, cruel, wise, clever, brace, selfish, crazy, good, careful, careless, impolite, right, wrong等。
It is very kind of you to help me.
區(qū)別It is important for us to learn English well.
4. 在某些動詞后, 可用it做形式賓語,然后加賓語補足語,最后加不定式作真正的賓語。
常見的動詞有find, think consider, feel, make等。
They find it difficult to repay the money.
5. 動詞+不定式作賓補
ask, want, invite, get, force, expect, allow, persuade, order, warn, remind order, cause, permit, forbid, advise, teach等。
6. 在使役動詞make, have, let和感官動詞see, watch, notice, observe, feel, hear, listen to, look at等詞后接不定式作賓補,不定式不帶to,表示做某事的全過程。當他們轉(zhuǎn)換成被動語態(tài)時,作為主語補足語的不定式必須帶to(五看三使兩聽一感覺一發(fā)現(xiàn))
Nobody saw him come in.
She was seen to enter the room last night.
注意:get 也能當使役動詞,表示“使、讓、叫”之意,相當于have,但兩者也有所不同。
have sb. do sth.get sb to do sth.使/讓/叫某人去做某事
have sth. done = get sth. done 使/讓某事由別人去做
have sb./sth. doing 使/讓某人/物持續(xù)地做某事
get sb./ sth.dong 使某人/物開始行動起來
You’d better have/get your hair cut.
He managed to get the horse running.