I.be作為助動詞可以:
1.構成進行時態(tài)(be+現(xiàn)在分詞)
I am seeing a friend off.
我在給一個朋友送行。
She was telling us a story.
她在給我們講故事。
He will be leaving tomorrow.
他明天走。
What have you been doing these days?
這些時候你都在干什么?
2.構被動語態(tài)(be+過去分詞):
These books were published last year.
這些書是去年山版的。
Rice is grown chiefly in the south.
水稻主要在南方種植。
The houses are being rebuilt.
這些房了正在重建。
The plan has been approved.
計劃業(yè)已批準。
此外還可以和不定式構成復合謂語表示打算做或應該做的事:
Where are we to meet?
我們在哪里碰頭?
Who is to pay?
誰付錢?
You're to be back tonight.
你應今晚回來。
The worst was still to come.
最糟糕的情況還在后頭。
II.have作為助動詞可以:
1.構成完成時態(tài)(have+過去分詞):
What has happened?
出了什么事?
He told me Jane had left.
他告訴我簡已經(jīng)走了。
She will have arrived by this time tomorrow.
明天這時她就會到了。
How long have you been there?
你在那里待了多久?
2.構成完成進行時態(tài)(have+been+現(xiàn)在分詞)
We have been trying to contact you.
我們一直在想和你聯(lián)系。
She has been teaching there for thirty years.
她在那里任教達三十年。
That was the book he had been looking for.
這是他一直在找的書。
另外,have (got)to還可構成謂語,表示“不得不”:
We have (got) to be careful.
我們得小心。
You don't have to worry.
你不必憂慮。