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