I may curb you may curb he may curb we may curb you may curb they may curb
V-ing form
I may be curbing you may be curbing he may be curbing we may be curbing you may be curbing they may be curbing
Perfect
I may have curbed you may have curbed he may have curbed we may have curbed you may have curbed they may have curbed
V-ing perfect
I may have been curbing you may have been curbing he may have been curbing we may have been curbing you may have been curbing they may have been curbing
Negation
Simple form
I may not curb you may not curb he may not curb we may not curb you may not curb they may not curb
V-ing form
I may not be curbing you may not be curbing he may not be curbing we may not be curbing you may not be curbing they may not be curbing
Perfect
I may not have curbed you may not have curbed he may not have curbed we may not have curbed you may not have curbed they may not have curbed
V-ing perfect
I may not have been curbing you may not have been curbing he may not have been curbing we may not have been curbing you may not have been curbing they may not have been curbing
Interrogative form
Simple form
may I curb? may you curb? may he curb? may we curb? may you curb? may they curb?
V-ing form
may I be curbing? may you be curbing? may he be curbing? may we be curbing? may you be curbing? may they be curbing?
Perfect
may I have curbed? may you have curbed? may he have curbed? may we have curbed? may you have curbed? may they have curbed?
V-ing perfect
may I have been curbing? may you have been curbing? may he have been curbing? may we have been curbing? may you have been curbing? may they have been curbing?
Interro-negative form
Simple form
may I not curb? may you not curb? may he not curb? may we not curb? may you not curb? may they not curb?
V-ing form
may I not be curbing? may you not be curbing? may he not be curbing? may we not be curbing? may you not be curbing? may they not be curbing?
Perfect
may I not have curbed? may you not have curbed? may he not have curbed? may we not have curbed? may you not have curbed? may they not have curbed?
V-ing perfect
may I not have been curbing? may you not have been curbing? may he not have been curbing? may we not have been curbing? may you not have been curbing? may they not have been curbing?