IMPERATIVE
 

Form
The imperative has the same form as the infinitive without to

  • Sit down.
 
Use
a - To give orders, to make suggestions and requests, and to give warnings.
Stop at the sign. "Look over there." Be careful up there.
 
b - We make the negative imperative with do not/don't.
Don't park here. Don't open the window. Don't walk on the grass.
 
c - We can make an imperative more emphatic* by putting do in front of it. (politeness, impatience, ...)
Do keep quiet. Do clean your room.

* emphatic: put the stress on it