I must participate you must participate he must participate we must participate you must participate they must participate
V-ing form
I must be participating you must be participating he must be participating we must be participating you must be participating they must be participating
Perfect
I must have participated you must have participated he must have participated we must have participated you must have participated they must have participated
V-ing perfect
I must have been participating you must have been participating he must have been participating we must have been participating you must have been participating they must have been participating
Negation
Simple form
I must not participate you must not participate he must not participate we must not participate you must not participate they must not participate
V-ing form
I must not be participating you must not be participating he must not be participating we must not be participating you must not be participating they must not be participating
Perfect
I must not have participated you must not have participated he must not have participated we must not have participated you must not have participated they must not have participated
V-ing perfect
I must not have been participating you must not have been participating he must not have been participating we must not have been participating you must not have been participating they must not have been participating
Interrogative form
Simple form
must I participate? must you participate? must he participate? must we participate? must you participate? must they participate?
V-ing form
must I be participating? must you be participating? must he be participating? must we be participating? must you be participating? must they be participating?
Perfect
must I have participated? must you have participated? must he have participated? must we have participated? must you have participated? must they have participated?
V-ing perfect
must I have been participating? must you have been participating? must he have been participating? must we have been participating? must you have been participating? must they have been participating?
Interro-negative form
Simple form
must I not participate? must you not participate? must he not participate? must we not participate? must you not participate? must they not participate?
V-ing form
must I not be participating? must you not be participating? must he not be participating? must we not be participating? must you not be participating? must they not be participating?
Perfect
must I not have participated? must you not have participated? must he not have participated? must we not have participated? must you not have participated? must they not have participated?
V-ing perfect
must I not have been participating? must you not have been participating? must he not have been participating? must we not have been participating? must you not have been participating? must they not have been participating?