English verb conjugation
COULD DUET

Regular verb: duet - dueted - dueted

Affirmation

Simple form	V-ing form
I could duet you could duet he could duet we could duet you could duet they could duet	I could be dueting you could be dueting he could be dueting we could be dueting you could be dueting they could be dueting
Perfect	V-ing perfect
I could have dueted you could have dueted he could have dueted we could have dueted you could have dueted they could have dueted	I could have been dueting you could have been dueting he could have been dueting we could have been dueting you could have been dueting they could have been dueting

Negation

Simple form	V-ing form
I couldn't duet you couldn't duet he couldn't duet we couldn't duet you couldn't duet they couldn't duet	I couldn't be dueting you couldn't be dueting he couldn't be dueting we couldn't be dueting you couldn't be dueting they couldn't be dueting
Perfect	V-ing perfect
I couldn't have dueted you couldn't have dueted he couldn't have dueted we couldn't have dueted you couldn't have dueted they couldn't have dueted	I couldn't have been dueting you couldn't have been dueting he couldn't have been dueting we couldn't have been dueting you couldn't have been dueting they couldn't have been dueting

Interrogative form

Simple form	V-ing form
could I duet? could you duet? could he duet? could we duet? could you duet? could they duet?	could I be dueting? could you be dueting? could he be dueting? could we be dueting? could you be dueting? could they be dueting?
Perfect	V-ing perfect
could I have dueted? could you have dueted? could he have dueted? could we have dueted? could you have dueted? could they have dueted?	could I have been dueting? could you have been dueting? could he have been dueting? could we have been dueting? could you have been dueting? could they have been dueting?

Interro-negative form

Simple form	V-ing form
couldn't I duet? couldn't you duet? couldn't he duet? couldn't we duet? couldn't you duet? couldn't they duet?	couldn't I be dueting? couldn't you be dueting? couldn't he be dueting? couldn't we be dueting? couldn't you be dueting? couldn't they be dueting?
Perfect	V-ing perfect
couldn't I have dueted? couldn't you have dueted? couldn't he have dueted? couldn't we have dueted? couldn't you have dueted? couldn't they have dueted?	couldn't I have been dueting? couldn't you have been dueting? couldn't he have been dueting? couldn't we have been dueting? couldn't you have been dueting? couldn't they have been dueting?