I must plug you must plug he must plug we must plug you must plug they must plug
V-ing form
I must be plugging you must be plugging he must be plugging we must be plugging you must be plugging they must be plugging
Perfect
I must have plugged you must have plugged he must have plugged we must have plugged you must have plugged they must have plugged
V-ing perfect
I must have been plugging you must have been plugging he must have been plugging we must have been plugging you must have been plugging they must have been plugging
Negation
Simple form
I must not plug you must not plug he must not plug we must not plug you must not plug they must not plug
V-ing form
I must not be plugging you must not be plugging he must not be plugging we must not be plugging you must not be plugging they must not be plugging
Perfect
I must not have plugged you must not have plugged he must not have plugged we must not have plugged you must not have plugged they must not have plugged
V-ing perfect
I must not have been plugging you must not have been plugging he must not have been plugging we must not have been plugging you must not have been plugging they must not have been plugging
Interrogative form
Simple form
must I plug? must you plug? must he plug? must we plug? must you plug? must they plug?
V-ing form
must I be plugging? must you be plugging? must he be plugging? must we be plugging? must you be plugging? must they be plugging?
Perfect
must I have plugged? must you have plugged? must he have plugged? must we have plugged? must you have plugged? must they have plugged?
V-ing perfect
must I have been plugging? must you have been plugging? must he have been plugging? must we have been plugging? must you have been plugging? must they have been plugging?
Interro-negative form
Simple form
must I not plug? must you not plug? must he not plug? must we not plug? must you not plug? must they not plug?
V-ing form
must I not be plugging? must you not be plugging? must he not be plugging? must we not be plugging? must you not be plugging? must they not be plugging?
Perfect
must I not have plugged? must you not have plugged? must he not have plugged? must we not have plugged? must you not have plugged? must they not have plugged?
V-ing perfect
must I not have been plugging? must you not have been plugging? must he not have been plugging? must we not have been plugging? must you not have been plugging? must they not have been plugging?