English verb conjugation
COULD MUFF

Regular verb: muff - muffed - muffed

Affirmation

Simple form	V-ing form
I could muff you could muff he could muff we could muff you could muff they could muff	I could be muffing you could be muffing he could be muffing we could be muffing you could be muffing they could be muffing
Perfect	V-ing perfect
I could have muffed you could have muffed he could have muffed we could have muffed you could have muffed they could have muffed	I could have been muffing you could have been muffing he could have been muffing we could have been muffing you could have been muffing they could have been muffing

Negation

Simple form	V-ing form
I could not muff you could not muff he could not muff we could not muff you could not muff they could not muff	I could not be muffing you could not be muffing he could not be muffing we could not be muffing you could not be muffing they could not be muffing
Perfect	V-ing perfect
I could not have muffed you could not have muffed he could not have muffed we could not have muffed you could not have muffed they could not have muffed	I could not have been muffing you could not have been muffing he could not have been muffing we could not have been muffing you could not have been muffing they could not have been muffing

Interrogative form

Simple form	V-ing form
could I muff? could you muff? could he muff? could we muff? could you muff? could they muff?	could I be muffing? could you be muffing? could he be muffing? could we be muffing? could you be muffing? could they be muffing?
Perfect	V-ing perfect
could I have muffed? could you have muffed? could he have muffed? could we have muffed? could you have muffed? could they have muffed?	could I have been muffing? could you have been muffing? could he have been muffing? could we have been muffing? could you have been muffing? could they have been muffing?

Interro-negative form

Simple form	V-ing form
could I not muff? could you not muff? could he not muff? could we not muff? could you not muff? could they not muff?	could I not be muffing? could you not be muffing? could he not be muffing? could we not be muffing? could you not be muffing? could they not be muffing?
Perfect	V-ing perfect
could I not have muffed? could you not have muffed? could he not have muffed? could we not have muffed? could you not have muffed? could they not have muffed?	could I not have been muffing? could you not have been muffing? could he not have been muffing? could we not have been muffing? could you not have been muffing? could they not have been muffing?