I must fly you must fly he must fly we must fly you must fly they must fly
V-ing form
I must be flying you must be flying he must be flying we must be flying you must be flying they must be flying
Perfect
I must have flown you must have flown he must have flown we must have flown you must have flown they must have flown
V-ing perfect
I must have been flying you must have been flying he must have been flying we must have been flying you must have been flying they must have been flying
Negation
Simple form
I must not fly you must not fly he must not fly we must not fly you must not fly they must not fly
V-ing form
I must not be flying you must not be flying he must not be flying we must not be flying you must not be flying they must not be flying
Perfect
I must not have flown you must not have flown he must not have flown we must not have flown you must not have flown they must not have flown
V-ing perfect
I must not have been flying you must not have been flying he must not have been flying we must not have been flying you must not have been flying they must not have been flying
Interrogative form
Simple form
must I fly? must you fly? must he fly? must we fly? must you fly? must they fly?
V-ing form
must I be flying? must you be flying? must he be flying? must we be flying? must you be flying? must they be flying?
Perfect
must I have flown? must you have flown? must he have flown? must we have flown? must you have flown? must they have flown?
V-ing perfect
must I have been flying? must you have been flying? must he have been flying? must we have been flying? must you have been flying? must they have been flying?
Interro-negative form
Simple form
must I not fly? must you not fly? must he not fly? must we not fly? must you not fly? must they not fly?
V-ing form
must I not be flying? must you not be flying? must he not be flying? must we not be flying? must you not be flying? must they not be flying?
Perfect
must I not have flown? must you not have flown? must he not have flown? must we not have flown? must you not have flown? must they not have flown?
V-ing perfect
must I not have been flying? must you not have been flying? must he not have been flying? must we not have been flying? must you not have been flying? must they not have been flying?