English verb conjugation
COULD PLUMP

Regular verb: plump - plumped - plumped

Affirmation

Simple form	V-ing form
I could plump you could plump he could plump we could plump you could plump they could plump	I could be plumping you could be plumping he could be plumping we could be plumping you could be plumping they could be plumping
Perfect	V-ing perfect
I could have plumped you could have plumped he could have plumped we could have plumped you could have plumped they could have plumped	I could have been plumping you could have been plumping he could have been plumping we could have been plumping you could have been plumping they could have been plumping

Negation

Simple form	V-ing form
I could not plump you could not plump he could not plump we could not plump you could not plump they could not plump	I could not be plumping you could not be plumping he could not be plumping we could not be plumping you could not be plumping they could not be plumping
Perfect	V-ing perfect
I could not have plumped you could not have plumped he could not have plumped we could not have plumped you could not have plumped they could not have plumped	I could not have been plumping you could not have been plumping he could not have been plumping we could not have been plumping you could not have been plumping they could not have been plumping

Interrogative form

Simple form	V-ing form
could I plump? could you plump? could he plump? could we plump? could you plump? could they plump?	could I be plumping? could you be plumping? could he be plumping? could we be plumping? could you be plumping? could they be plumping?
Perfect	V-ing perfect
could I have plumped? could you have plumped? could he have plumped? could we have plumped? could you have plumped? could they have plumped?	could I have been plumping? could you have been plumping? could he have been plumping? could we have been plumping? could you have been plumping? could they have been plumping?

Interro-negative form

Simple form	V-ing form
could I not plump? could you not plump? could he not plump? could we not plump? could you not plump? could they not plump?	could I not be plumping? could you not be plumping? could he not be plumping? could we not be plumping? could you not be plumping? could they not be plumping?
Perfect	V-ing perfect
could I not have plumped? could you not have plumped? could he not have plumped? could we not have plumped? could you not have plumped? could they not have plumped?	could I not have been plumping? could you not have been plumping? could he not have been plumping? could we not have been plumping? could you not have been plumping? could they not have been plumping?