The Infinitive without to

after auxiliaries / modals

Can	He can run very fast.
Could	As a boy he could runvery fast.
May	I may fly to Africa this summer.
Might	I might fly to africa this summer.
Must	I must go now.
Mustn't	You mustn't smoke here.
Needn't	You needn't go.
Shall	We shall sing a song.
Should	We should sing a song.
Will	She will cook a meal for his birthday.
Would	She would cook a meal for his birthday.

after to do

Do	I don't know.

after the following expressions:

Had better	You had better clean up your room.
Would rather	Susan would rather study for her exam tomorrow.
Would sooner	I would sooner read a book than watch this film.
Why not	Why not ask your neighbour for help?
Why should we	Why should we go by car?
Why should we not	Why should we not go by car?

after verbs of perception + object (action has finished):

Feel	She feels the rain fall on her face.
Hear	I heard Peter sing a song.
Notice	Mandy noticed the boy climb the tree.
See	They saw him climb up the roof.
Watch	He watched the thieves steal a car.

after let + object:

Let	Sandy let her child go out alone.
	Mother let her daughter decide on her own.
Let's	Let's go for a walk through the park.

after make + object:

make	She made Peggy and Samantha clean the room.