學習重點：modal Auxliaries in the past 情態動詞的過去式
Some Used of Modals in the Past 情態動詞過去時的一些用法
Modal Auxiliaries in the Past 情態動詞的過去時
情態動詞的過去時可以用have和過去分詞表示：
我們來把一些情態動詞的現在形式和其過去形式做一下對照。下個單元里會列舉其他的情態動詞。
*這里的have一般不發/hQv/音，而發/hEv/和/Ev/音
（/hEv/只用在肯定句里）。
現在 肯定句
|
主語 |
情態動詞 |
不定式 |
|
Ｉ
We
You
They
He/She/It |
may
might
could
would
should |
do it.
ask him.
|
|
ought to |
現在 否定句（縮略形式）
|
主語 |
情態動詞 |
不定式 |
|
Ｉ
We
You
They
He/She/It |
may not
might not(mightn’t)
could not(couldn’t)
would not(wouldn’t)
should not(shouldn’t) |
do it.
ask him.
|
|
ought not to(oughtn’t to) |
現在 疑問句
|
情態動詞 |
主語 |
|
不定式 |
|
May
Might
Could
Would
Could
Would
Should
Ought |
I
we
you
they
he/she/it |
to |
do it?
ask him?
|
過去 肯定句
|
主語 |
情態動詞 |
have |
不定式 |
|
Ｉ
Ｗe
You
They
He/She/It |
May
Might
Could
Would
should |
have
|
Done it.
Asked him.
|
|
Ought to |
過去 否定句
|
主語 |
情態動詞 |
have |
不定式 |
|
I
We
You
They
He/She?it |
May not
Might not(mightn’t)
Could not(couldn’t)
Would not(wouldn’t)
Should not(shouldn’t)
Ought not to(oughtn’t to) |
have
|
done it.
Asked him.
|
過去 疑問句
|
情態動詞 |
主語 |
|
have |
不定式 |
|
May
Might
Could
Would
Should |
I
we
you
they
he/she/it |
|
have
|
done
asked him?
|
|
Ought |
to |
Some Yses of Modal in the Past 情態動詞過去時的一些用法
must have can’t have
●如第３單元所說，以過去事實為基礎進行推測時可以用must have(肯定)和can’t have(否定)
When did we last meet?我們上次見面是什么時候？
-It must have been before 1990, because I got married in 1990.一定是１９９０年之前，因為我１９９０年結的婚。
The woman I saw was wearing pink trousers.我看見的那個女人穿著一條粉色的褲子。
-It can’t have been my wife. She never weras pink.那一定不是我妻子，她從來不穿粉色的衣服。
May have 和might have表示“過去可能發生了某事，但不確定”。
-I don’t know. She may/might have gone home.我不知道。她可能已經回家了。
Why hasn’t John arrived yet?為什么約翰還沒有來？
-He may/might have got lost.他可能迷路了。
●might have還可以對過去發生的事情，以假設為基礎，對其結果進行推測。
Why didn’t you eeeeeeeeeeeenter the competition? You might have won.你為什么不參加比賽呢？你會羸。
Why did you jump/ You might have been killed.你為什么不跳開？你差點兒被殺。
may have就沒有這種意思。
could have
could have有許多用法。
●可以像might have那樣，表示“過去可能發生的某事，但不確定”。
Where’s Ann?安在哪兒？
-I don’t know. She could have gone home. 我不知道，她可能回家了。
●could have還可以像might have那樣，對過去沒有發生的事情，以假設為基礎，對其結果進行推測。
You could have won.你可能會羸。
You could have been killed.你可能會被殺害
●couldn’t have表示過去“不可能發生某事”。
John couldn’t have killed the old woman. He was here with me.約翰不可能殺死那個老婦人。 他那時和我在一起。
should have和 ought have
●should have 和ought have表示“本來是做某事最好的方法，結果卻沒有做”。
I should have given him some money. ( but I didn’t. ) 我本應該給他一些錢。（但是我沒有給）
I ought to have told him he was an idiot, ( but I didn’t ).
我應該告訴他，他是一個白癡。（但是我沒有說）
You shouldn’t have talked to her, ( but you did ).你本不應該對他說。（但是我告訴了她）
You oughtn’t to have had a cigarette. (but you did).你本不應該吸煙。（但是你吸了）
●should have 和ought to have 還可以表示預計的事情沒有發生，但到底會不會發生自己也不知道。
Where are we?We ought to have seen signs to London by now.我們要在哪兒？現在我們應該看見到倫敦的路標了。
It’s 9:30.John should have arrived by now.現在是９點半。約翰應該已經到了。
