There are four options to use the modal verbs according to the same rules seen for the tenses above. The form after the modal is always infinitive (verb or auxiliaries "be" or "have").
Might (not) do Might (not) be doing
Might (not) have done Might (not) have been doing
Modal verbs work as auxiliaries:
Will you come tomorrow? Would she have done it?
What must teachers do? What might they be doing?
Would
If I had the time, I would do lots of things. I would hang out with my friends and we would play football.
They would be enjoying with us right now if they had come.
She wouldn't have accepted if you had asked her.
What would you like to drink? I'd like a coke, please.
At the beggining of August I started to train again and so I ‘d/would do mostly the same everyday. I ‘d/would meet my friends every morning and then I’d have lunch at home. In the afternoon I ‘d go to the swimming pool and then in the evening I ‘d go to train. After that, I ‘d go back home, have a shower and have dinner. Finally, I ‘d meet my friends until midnight and then go to bed.
Will
Negative : won't (will not)
I will tell her tomorrow. She won't be expecting it.
Will they have left by the time I come home?
Will you marry me? Yes, I will.
I told him many times but he won't do it!
Can/could
Can: Present
Could: Past simple and Conditionnal
I can/could play the guitar but I can't/couldn't play the piano. (ability/unability)
Can/ Could you lift this stone? (capacity)
This problem can't/couldn't be resolved. (possibility)
I could have helped you if you had asked me (conditionnal possibility/capacity)
He can't have done it, he wasn't there, (improbability/impossibility)
You can't smoke here! (prohibition, not allowed)
"Can" has no future form so "equivalents" are used instead
Equivalents
May/might
He may/might go to the cinema tonight. (future probability)
I might not be selected for the match tomorrow (future improbability)
They may/might have been sleeping when we called, (past probability)
Must
He must be sleeping, I can't hear him.
You must have been tired after that long journey.
You must do your homework!
They must do their job, it's their duty.
Equivalents
Mustn't
You mustn't cross the street when the light is red!
You mustn't tell lies!
Needn’t
You needn't worry, everything's fine!
You needn't have brought the book because I've got it.
Equivalents
Should, ought to
You should study more for the exams, (advice)
She shouldn't do that, it's dangerous.(advice)
They should have told me first! Now, it's too late! (reproach)
We shouldn't have been sleeping at that moment, (regret, reproach)
