English verb conjugation
COULD PAPER

Regular verb: paper - papered - papered

Affirmation

Simple form	V-ing form
I could paper you could paper he could paper we could paper you could paper they could paper	I could be papering you could be papering he could be papering we could be papering you could be papering they could be papering
Perfect	V-ing perfect
I could have papered you could have papered he could have papered we could have papered you could have papered they could have papered	I could have been papering you could have been papering he could have been papering we could have been papering you could have been papering they could have been papering

Negation

Simple form	V-ing form
I could not paper you could not paper he could not paper we could not paper you could not paper they could not paper	I could not be papering you could not be papering he could not be papering we could not be papering you could not be papering they could not be papering
Perfect	V-ing perfect
I could not have papered you could not have papered he could not have papered we could not have papered you could not have papered they could not have papered	I could not have been papering you could not have been papering he could not have been papering we could not have been papering you could not have been papering they could not have been papering

Interrogative form

Simple form	V-ing form
could I paper? could you paper? could he paper? could we paper? could you paper? could they paper?	could I be papering? could you be papering? could he be papering? could we be papering? could you be papering? could they be papering?
Perfect	V-ing perfect
could I have papered? could you have papered? could he have papered? could we have papered? could you have papered? could they have papered?	could I have been papering? could you have been papering? could he have been papering? could we have been papering? could you have been papering? could they have been papering?

Interro-negative form

Simple form	V-ing form
could I not paper? could you not paper? could he not paper? could we not paper? could you not paper? could they not paper?	could I not be papering? could you not be papering? could he not be papering? could we not be papering? could you not be papering? could they not be papering?
Perfect	V-ing perfect
could I not have papered? could you not have papered? could he not have papered? could we not have papered? could you not have papered? could they not have papered?	could I not have been papering? could you not have been papering? could he not have been papering? could we not have been papering? could you not have been papering? could they not have been papering?