English verb conjugation
COULD DRUM

Regular verb: drum - drummed - drummed

Affirmation

Simple form	V-ing form
I could drum you could drum he could drum we could drum you could drum they could drum	I could be drumming you could be drumming he could be drumming we could be drumming you could be drumming they could be drumming
Perfect	V-ing perfect
I could have drummed you could have drummed he could have drummed we could have drummed you could have drummed they could have drummed	I could have been drumming you could have been drumming he could have been drumming we could have been drumming you could have been drumming they could have been drumming

Negation

Simple form	V-ing form
I could not drum you could not drum he could not drum we could not drum you could not drum they could not drum	I could not be drumming you could not be drumming he could not be drumming we could not be drumming you could not be drumming they could not be drumming
Perfect	V-ing perfect
I could not have drummed you could not have drummed he could not have drummed we could not have drummed you could not have drummed they could not have drummed	I could not have been drumming you could not have been drumming he could not have been drumming we could not have been drumming you could not have been drumming they could not have been drumming

Interrogative form

Simple form	V-ing form
could I drum? could you drum? could he drum? could we drum? could you drum? could they drum?	could I be drumming? could you be drumming? could he be drumming? could we be drumming? could you be drumming? could they be drumming?
Perfect	V-ing perfect
could I have drummed? could you have drummed? could he have drummed? could we have drummed? could you have drummed? could they have drummed?	could I have been drumming? could you have been drumming? could he have been drumming? could we have been drumming? could you have been drumming? could they have been drumming?

Interro-negative form

Simple form	V-ing form
could I not drum? could you not drum? could he not drum? could we not drum? could you not drum? could they not drum?	could I not be drumming? could you not be drumming? could he not be drumming? could we not be drumming? could you not be drumming? could they not be drumming?
Perfect	V-ing perfect
could I not have drummed? could you not have drummed? could he not have drummed? could we not have drummed? could you not have drummed? could they not have drummed?	could I not have been drumming? could you not have been drumming? could he not have been drumming? could we not have been drumming? could you not have been drumming? could they not have been drumming?