I must perform you must perform she must perform we must perform you must perform they must perform
V-ing form
I must be performing you must be performing she must be performing we must be performing you must be performing they must be performing
Perfect
I must have performed you must have performed she must have performed we must have performed you must have performed they must have performed
V-ing perfect
I must have been performing you must have been performing she must have been performing we must have been performing you must have been performing they must have been performing
Negation
Simple form
I must not perform you must not perform she must not perform we must not perform you must not perform they must not perform
V-ing form
I must not be performing you must not be performing she must not be performing we must not be performing you must not be performing they must not be performing
Perfect
I must not have performed you must not have performed she must not have performed we must not have performed you must not have performed they must not have performed
V-ing perfect
I must not have been performing you must not have been performing she must not have been performing we must not have been performing you must not have been performing they must not have been performing
Interrogative form
Simple form
must I perform? must you perform? must she perform? must we perform? must you perform? must they perform?
V-ing form
must I be performing? must you be performing? must she be performing? must we be performing? must you be performing? must they be performing?
Perfect
must I have performed? must you have performed? must she have performed? must we have performed? must you have performed? must they have performed?
V-ing perfect
must I have been performing? must you have been performing? must she have been performing? must we have been performing? must you have been performing? must they have been performing?
Interro-negative form
Simple form
must I not perform? must you not perform? must she not perform? must we not perform? must you not perform? must they not perform?
V-ing form
must I not be performing? must you not be performing? must she not be performing? must we not be performing? must you not be performing? must they not be performing?
Perfect
must I not have performed? must you not have performed? must she not have performed? must we not have performed? must you not have performed? must they not have performed?
V-ing perfect
must I not have been performing? must you not have been performing? must she not have been performing? must we not have been performing? must you not have been performing? must they not have been performing?