English verb conjugation
COULD REFUTE

Regular verb: refute - refuted - refuted

Affirmation

Simple form	V-ing form
I could refute you could refute he could refute we could refute you could refute they could refute	I could be refuting you could be refuting he could be refuting we could be refuting you could be refuting they could be refuting
Perfect	V-ing perfect
I could have refuted you could have refuted he could have refuted we could have refuted you could have refuted they could have refuted	I could have been refuting you could have been refuting he could have been refuting we could have been refuting you could have been refuting they could have been refuting

Negation

Simple form	V-ing form
I couldn't refute you couldn't refute he couldn't refute we couldn't refute you couldn't refute they couldn't refute	I couldn't be refuting you couldn't be refuting he couldn't be refuting we couldn't be refuting you couldn't be refuting they couldn't be refuting
Perfect	V-ing perfect
I couldn't have refuted you couldn't have refuted he couldn't have refuted we couldn't have refuted you couldn't have refuted they couldn't have refuted	I couldn't have been refuting you couldn't have been refuting he couldn't have been refuting we couldn't have been refuting you couldn't have been refuting they couldn't have been refuting

Interrogative form

Simple form	V-ing form
could I refute? could you refute? could he refute? could we refute? could you refute? could they refute?	could I be refuting? could you be refuting? could he be refuting? could we be refuting? could you be refuting? could they be refuting?
Perfect	V-ing perfect
could I have refuted? could you have refuted? could he have refuted? could we have refuted? could you have refuted? could they have refuted?	could I have been refuting? could you have been refuting? could he have been refuting? could we have been refuting? could you have been refuting? could they have been refuting?

Interro-negative form

Simple form	V-ing form
couldn't I refute? couldn't you refute? couldn't he refute? couldn't we refute? couldn't you refute? couldn't they refute?	couldn't I be refuting? couldn't you be refuting? couldn't he be refuting? couldn't we be refuting? couldn't you be refuting? couldn't they be refuting?
Perfect	V-ing perfect
couldn't I have refuted? couldn't you have refuted? couldn't he have refuted? couldn't we have refuted? couldn't you have refuted? couldn't they have refuted?	couldn't I have been refuting? couldn't you have been refuting? couldn't he have been refuting? couldn't we have been refuting? couldn't you have been refuting? couldn't they have been refuting?