English verb conjugation
COULD FLUSH

Regular verb: flush - flushed - flushed

Affirmation

Simple form	V-ing form
I could flush you could flush he could flush we could flush you could flush they could flush	I could be flushing you could be flushing he could be flushing we could be flushing you could be flushing they could be flushing
Perfect	V-ing perfect
I could have flushed you could have flushed he could have flushed we could have flushed you could have flushed they could have flushed	I could have been flushing you could have been flushing he could have been flushing we could have been flushing you could have been flushing they could have been flushing

Negation

Simple form	V-ing form
I could not flush you could not flush he could not flush we could not flush you could not flush they could not flush	I could not be flushing you could not be flushing he could not be flushing we could not be flushing you could not be flushing they could not be flushing
Perfect	V-ing perfect
I could not have flushed you could not have flushed he could not have flushed we could not have flushed you could not have flushed they could not have flushed	I could not have been flushing you could not have been flushing he could not have been flushing we could not have been flushing you could not have been flushing they could not have been flushing

Interrogative form

Simple form	V-ing form
could I flush? could you flush? could he flush? could we flush? could you flush? could they flush?	could I be flushing? could you be flushing? could he be flushing? could we be flushing? could you be flushing? could they be flushing?
Perfect	V-ing perfect
could I have flushed? could you have flushed? could he have flushed? could we have flushed? could you have flushed? could they have flushed?	could I have been flushing? could you have been flushing? could he have been flushing? could we have been flushing? could you have been flushing? could they have been flushing?

Interro-negative form

Simple form	V-ing form
could I not flush? could you not flush? could he not flush? could we not flush? could you not flush? could they not flush?	could I not be flushing? could you not be flushing? could he not be flushing? could we not be flushing? could you not be flushing? could they not be flushing?
Perfect	V-ing perfect
could I not have flushed? could you not have flushed? could he not have flushed? could we not have flushed? could you not have flushed? could they not have flushed?	could I not have been flushing? could you not have been flushing? could he not have been flushing? could we not have been flushing? could you not have been flushing? could they not have been flushing?