speculation and deduction Flashcards
(11 cards)
must
for obligation and strong recommendation, but also to say that we are quite sure that something is true.
They are almost identical. They must be sisters.
must be + –ing
to say that we are quite sure that something is happening now.
What you are saying is not possible. You must be kidding.
must have + past participle or must have been + -ing
to say that we are quite sure that something was true or happened in the past.
I can’t find my wallet! I must have dropped it in the taxi.
Can’t
to say that we are quite sure that something is NOT true.
He can’t be that famous. I’ve never heard his name before.
can’t be + –ing
to say that we are quite sure that something is NOT happening now.
They can’t be travelling by bus. There is no bus service on Sundays.
Could/might/may
o say that it’s possible that something is true (but we are not sure).
I can’t get hold of him on the phone. He could/might/may be away.
could/might/may be + –ing
o say that we are quite it’s possible that something is happening now (but we are not sure).
Tom isn’t at the office. He might/may be working from home today.
could/might/may have + past participle or might/may have been + -ing
to say that it’s possible that something was true or happened in the past.
It’s been three days. They could/might/may have finished painting the house by now.
could have + past participle
to say that something was possible in the past but did not happen.
He could have played in the first division but had a terrible injury.
Should/ought to
to talk about a situation that we expect to happen (present or future).
He should/ought to be home by now. He is always home before 7.
should have/ought to have + past participle
to talk about a situation expected to happen in the past. We can also use this form to express criticism.
He should/ought to have received the parcel yesterday. I sent it two days ago.
