I must billet you must billet he must billet we must billet you must billet they must billet
V-ing form
I must be billeting you must be billeting he must be billeting we must be billeting you must be billeting they must be billeting
Perfect
I must have billeted you must have billeted he must have billeted we must have billeted you must have billeted they must have billeted
V-ing perfect
I must have been billeting you must have been billeting he must have been billeting we must have been billeting you must have been billeting they must have been billeting
Negation
Simple form
I must not billet you must not billet he must not billet we must not billet you must not billet they must not billet
V-ing form
I must not be billeting you must not be billeting he must not be billeting we must not be billeting you must not be billeting they must not be billeting
Perfect
I must not have billeted you must not have billeted he must not have billeted we must not have billeted you must not have billeted they must not have billeted
V-ing perfect
I must not have been billeting you must not have been billeting he must not have been billeting we must not have been billeting you must not have been billeting they must not have been billeting
Interrogative form
Simple form
must I billet? must you billet? must he billet? must we billet? must you billet? must they billet?
V-ing form
must I be billeting? must you be billeting? must he be billeting? must we be billeting? must you be billeting? must they be billeting?
Perfect
must I have billeted? must you have billeted? must he have billeted? must we have billeted? must you have billeted? must they have billeted?
V-ing perfect
must I have been billeting? must you have been billeting? must he have been billeting? must we have been billeting? must you have been billeting? must they have been billeting?
Interro-negative form
Simple form
must I not billet? must you not billet? must he not billet? must we not billet? must you not billet? must they not billet?
V-ing form
must I not be billeting? must you not be billeting? must he not be billeting? must we not be billeting? must you not be billeting? must they not be billeting?
Perfect
must I not have billeted? must you not have billeted? must he not have billeted? must we not have billeted? must you not have billeted? must they not have billeted?
V-ing perfect
must I not have been billeting? must you not have been billeting? must he not have been billeting? must we not have been billeting? must you not have been billeting? must they not have been billeting?