English verb conjugation
COULD LIST

Regular verb: list - listed - listed

Affirmation

Simple form	V-ing form
I could list you could list he could list we could list you could list they could list	I could be listing you could be listing he could be listing we could be listing you could be listing they could be listing
Perfect	V-ing perfect
I could have listed you could have listed he could have listed we could have listed you could have listed they could have listed	I could have been listing you could have been listing he could have been listing we could have been listing you could have been listing they could have been listing

Negation

Simple form	V-ing form
I couldn't list you couldn't list he couldn't list we couldn't list you couldn't list they couldn't list	I couldn't be listing you couldn't be listing he couldn't be listing we couldn't be listing you couldn't be listing they couldn't be listing
Perfect	V-ing perfect
I couldn't have listed you couldn't have listed he couldn't have listed we couldn't have listed you couldn't have listed they couldn't have listed	I couldn't have been listing you couldn't have been listing he couldn't have been listing we couldn't have been listing you couldn't have been listing they couldn't have been listing

Interrogative form

Simple form	V-ing form
could I list? could you list? could he list? could we list? could you list? could they list?	could I be listing? could you be listing? could he be listing? could we be listing? could you be listing? could they be listing?
Perfect	V-ing perfect
could I have listed? could you have listed? could he have listed? could we have listed? could you have listed? could they have listed?	could I have been listing? could you have been listing? could he have been listing? could we have been listing? could you have been listing? could they have been listing?

Interro-negative form

Simple form	V-ing form
couldn't I list? couldn't you list? couldn't he list? couldn't we list? couldn't you list? couldn't they list?	couldn't I be listing? couldn't you be listing? couldn't he be listing? couldn't we be listing? couldn't you be listing? couldn't they be listing?
Perfect	V-ing perfect
couldn't I have listed? couldn't you have listed? couldn't he have listed? couldn't we have listed? couldn't you have listed? couldn't they have listed?	couldn't I have been listing? couldn't you have been listing? couldn't he have been listing? couldn't we have been listing? couldn't you have been listing? couldn't they have been listing?