I may stifle you may stifle she may stifle we may stifle you may stifle they may stifle
V-ing form
I may be stifling you may be stifling she may be stifling we may be stifling you may be stifling they may be stifling
Perfect
I may have stifled you may have stifled she may have stifled we may have stifled you may have stifled they may have stifled
V-ing perfect
I may have been stifling you may have been stifling she may have been stifling we may have been stifling you may have been stifling they may have been stifling
Negation
Simple form
I may not stifle you may not stifle she may not stifle we may not stifle you may not stifle they may not stifle
V-ing form
I may not be stifling you may not be stifling she may not be stifling we may not be stifling you may not be stifling they may not be stifling
Perfect
I may not have stifled you may not have stifled she may not have stifled we may not have stifled you may not have stifled they may not have stifled
V-ing perfect
I may not have been stifling you may not have been stifling she may not have been stifling we may not have been stifling you may not have been stifling they may not have been stifling
Interrogative form
Simple form
may I stifle? may you stifle? may she stifle? may we stifle? may you stifle? may they stifle?
V-ing form
may I be stifling? may you be stifling? may she be stifling? may we be stifling? may you be stifling? may they be stifling?
Perfect
may I have stifled? may you have stifled? may she have stifled? may we have stifled? may you have stifled? may they have stifled?
V-ing perfect
may I have been stifling? may you have been stifling? may she have been stifling? may we have been stifling? may you have been stifling? may they have been stifling?
Interro-negative form
Simple form
may I not stifle? may you not stifle? may she not stifle? may we not stifle? may you not stifle? may they not stifle?
V-ing form
may I not be stifling? may you not be stifling? may she not be stifling? may we not be stifling? may you not be stifling? may they not be stifling?
Perfect
may I not have stifled? may you not have stifled? may she not have stifled? may we not have stifled? may you not have stifled? may they not have stifled?
V-ing perfect
may I not have been stifling? may you not have been stifling? may she not have been stifling? may we not have been stifling? may you not have been stifling? may they not have been stifling?