MODALS with MULTIPLE USES

To show that something was probable in the past:

VERY CERTAIN

must (not) have V3

can’t have V3

couldn’t have V3

Jack had a stomachache after dinner.

Sofia was at a movie with me last night.

He must have eaten too much.

You couldn’t have seen her at the mall.

To show that something was possible in the past:

UNCERTAIN

could have V3

may (not) have V3

might (not) have

V3

He could/may/might have missed the bus this morning.

Tanya was supposed to meet me before school.

David is usually here by now.

She may/might not have gotten the message.

PAST

must (not) V1

have to V1

have got to V1

had better (not) V1

should (not) V1

OPINION or ADVICE

PRESENT

should (not) have

V3

Parents have got to monitor the shows their children watch.

The kids have better not spend so much time indoors playing computer games.

I should have listened the advice my parents gave me about having a healhty life.

We should not have ignored the scientists’ warnings about global warming.

THANKS

thechadash