English verb conjugation
COULD FLUB

Regular verb: flub - flubed - flubed

Affirmation

Simple form	V-ing form
I could flub you could flub he could flub we could flub you could flub they could flub	I could be flubing you could be flubing he could be flubing we could be flubing you could be flubing they could be flubing
Perfect	V-ing perfect
I could have flubed you could have flubed he could have flubed we could have flubed you could have flubed they could have flubed	I could have been flubing you could have been flubing he could have been flubing we could have been flubing you could have been flubing they could have been flubing

Negation

Simple form	V-ing form
I couldn't flub you couldn't flub he couldn't flub we couldn't flub you couldn't flub they couldn't flub	I couldn't be flubing you couldn't be flubing he couldn't be flubing we couldn't be flubing you couldn't be flubing they couldn't be flubing
Perfect	V-ing perfect
I couldn't have flubed you couldn't have flubed he couldn't have flubed we couldn't have flubed you couldn't have flubed they couldn't have flubed	I couldn't have been flubing you couldn't have been flubing he couldn't have been flubing we couldn't have been flubing you couldn't have been flubing they couldn't have been flubing

Interrogative form

Simple form	V-ing form
could I flub? could you flub? could he flub? could we flub? could you flub? could they flub?	could I be flubing? could you be flubing? could he be flubing? could we be flubing? could you be flubing? could they be flubing?
Perfect	V-ing perfect
could I have flubed? could you have flubed? could he have flubed? could we have flubed? could you have flubed? could they have flubed?	could I have been flubing? could you have been flubing? could he have been flubing? could we have been flubing? could you have been flubing? could they have been flubing?

Interro-negative form

Simple form	V-ing form
couldn't I flub? couldn't you flub? couldn't he flub? couldn't we flub? couldn't you flub? couldn't they flub?	couldn't I be flubing? couldn't you be flubing? couldn't he be flubing? couldn't we be flubing? couldn't you be flubing? couldn't they be flubing?
Perfect	V-ing perfect
couldn't I have flubed? couldn't you have flubed? couldn't he have flubed? couldn't we have flubed? couldn't you have flubed? couldn't they have flubed?	couldn't I have been flubing? couldn't you have been flubing? couldn't he have been flubing? couldn't we have been flubing? couldn't you have been flubing? couldn't they have been flubing?