I must duel you must duel he must duel we must duel you must duel they must duel
V-ing form
I must be dueling you must be dueling he must be dueling we must be dueling you must be dueling they must be dueling
Perfect
I must have dueled you must have dueled he must have dueled we must have dueled you must have dueled they must have dueled
V-ing perfect
I must have been dueling you must have been dueling he must have been dueling we must have been dueling you must have been dueling they must have been dueling
Negation
Simple form
I must not duel you must not duel he must not duel we must not duel you must not duel they must not duel
V-ing form
I must not be dueling you must not be dueling he must not be dueling we must not be dueling you must not be dueling they must not be dueling
Perfect
I must not have dueled you must not have dueled he must not have dueled we must not have dueled you must not have dueled they must not have dueled
V-ing perfect
I must not have been dueling you must not have been dueling he must not have been dueling we must not have been dueling you must not have been dueling they must not have been dueling
Interrogative form
Simple form
must I duel? must you duel? must he duel? must we duel? must you duel? must they duel?
V-ing form
must I be dueling? must you be dueling? must he be dueling? must we be dueling? must you be dueling? must they be dueling?
Perfect
must I have dueled? must you have dueled? must he have dueled? must we have dueled? must you have dueled? must they have dueled?
V-ing perfect
must I have been dueling? must you have been dueling? must he have been dueling? must we have been dueling? must you have been dueling? must they have been dueling?
Interro-negative form
Simple form
must I not duel? must you not duel? must he not duel? must we not duel? must you not duel? must they not duel?
V-ing form
must I not be dueling? must you not be dueling? must he not be dueling? must we not be dueling? must you not be dueling? must they not be dueling?
Perfect
must I not have dueled? must you not have dueled? must he not have dueled? must we not have dueled? must you not have dueled? must they not have dueled?
V-ing perfect
must I not have been dueling? must you not have been dueling? must he not have been dueling? must we not have been dueling? must you not have been dueling? must they not have been dueling?