English verb conjugation
COULD LUFF

Regular verb: luff - luffed - luffed

Affirmation

Simple form	V-ing form
I could luff you could luff she could luff we could luff you could luff they could luff	I could be luffing you could be luffing she could be luffing we could be luffing you could be luffing they could be luffing
Perfect	V-ing perfect
I could have luffed you could have luffed she could have luffed we could have luffed you could have luffed they could have luffed	I could have been luffing you could have been luffing she could have been luffing we could have been luffing you could have been luffing they could have been luffing

Negation

Simple form	V-ing form
I could not luff you could not luff she could not luff we could not luff you could not luff they could not luff	I could not be luffing you could not be luffing she could not be luffing we could not be luffing you could not be luffing they could not be luffing
Perfect	V-ing perfect
I could not have luffed you could not have luffed she could not have luffed we could not have luffed you could not have luffed they could not have luffed	I could not have been luffing you could not have been luffing she could not have been luffing we could not have been luffing you could not have been luffing they could not have been luffing

Interrogative form

Simple form	V-ing form
could I luff? could you luff? could she luff? could we luff? could you luff? could they luff?	could I be luffing? could you be luffing? could she be luffing? could we be luffing? could you be luffing? could they be luffing?
Perfect	V-ing perfect
could I have luffed? could you have luffed? could she have luffed? could we have luffed? could you have luffed? could they have luffed?	could I have been luffing? could you have been luffing? could she have been luffing? could we have been luffing? could you have been luffing? could they have been luffing?

Interro-negative form

Simple form	V-ing form
could I not luff? could you not luff? could she not luff? could we not luff? could you not luff? could they not luff?	could I not be luffing? could you not be luffing? could she not be luffing? could we not be luffing? could you not be luffing? could they not be luffing?
Perfect	V-ing perfect
could I not have luffed? could you not have luffed? could she not have luffed? could we not have luffed? could you not have luffed? could they not have luffed?	could I not have been luffing? could you not have been luffing? could she not have been luffing? could we not have been luffing? could you not have been luffing? could they not have been luffing?