Page 4 - CFEM_TD2LOE_ingles_unit5

Sheila must have left two days ago

COULD and MUST in the past are used to indicate deduction. MUST is more certain than
COULD

Mike could have stayed in this hotel (it is possible that he stayed in this hotel)

Mike must have stayed in this hotel (it is almost definite that he stayed in this hotel)

CAN´T HAVE and COULDN´T HAVE indicate a negative deduction:

Mike can´t have stayed in this hotel (it is almost definite he didn´t stay in this hotel)

COULD HAVE means something that was possible, but it wasn´t done:

I could have left at ten o´clock, but I didn´t .

COULD + INFINITIVE means ability or possibility in the present or the future:

I could do it if you wanted me to

WOULD + INFINITIVE means a conditional intention in the present or the future:

I would do it if I were able to

MIGHT + INFINITIVE means possibility in the present or the future:

I might do it

MODALS are used to do things like talking about ability, asking permission making requests,
and so on.

Ability:

We use can to talk about someone’s skill or general abilities:

She can speak several languages.
He can swim like a fish.
They can’t dance very well.

We use can to talk about the ability to do something at a given time in the present or future:

You can make a lot of money if you are lucky.
Help. I can’t breathe.
They can run but they can’t hide.

We use could to talk about past time: