I must block you must block he must block we must block you must block they must block
V-ing form
I must be blocking you must be blocking he must be blocking we must be blocking you must be blocking they must be blocking
Perfect
I must have blocked you must have blocked he must have blocked we must have blocked you must have blocked they must have blocked
V-ing perfect
I must have been blocking you must have been blocking he must have been blocking we must have been blocking you must have been blocking they must have been blocking
Negation
Simple form
I must not block you must not block he must not block we must not block you must not block they must not block
V-ing form
I must not be blocking you must not be blocking he must not be blocking we must not be blocking you must not be blocking they must not be blocking
Perfect
I must not have blocked you must not have blocked he must not have blocked we must not have blocked you must not have blocked they must not have blocked
V-ing perfect
I must not have been blocking you must not have been blocking he must not have been blocking we must not have been blocking you must not have been blocking they must not have been blocking
Interrogative form
Simple form
must I block? must you block? must he block? must we block? must you block? must they block?
V-ing form
must I be blocking? must you be blocking? must he be blocking? must we be blocking? must you be blocking? must they be blocking?
Perfect
must I have blocked? must you have blocked? must he have blocked? must we have blocked? must you have blocked? must they have blocked?
V-ing perfect
must I have been blocking? must you have been blocking? must he have been blocking? must we have been blocking? must you have been blocking? must they have been blocking?
Interro-negative form
Simple form
must I not block? must you not block? must he not block? must we not block? must you not block? must they not block?
V-ing form
must I not be blocking? must you not be blocking? must he not be blocking? must we not be blocking? must you not be blocking? must they not be blocking?
Perfect
must I not have blocked? must you not have blocked? must he not have blocked? must we not have blocked? must you not have blocked? must they not have blocked?
V-ing perfect
must I not have been blocking? must you not have been blocking? must he not have been blocking? must we not have been blocking? must you not have been blocking? must they not have been blocking?