English verb conjugation
COULD GROWL

Regular verb: growl - growled - growled

Affirmation

Simple form	V-ing form
I could growl you could growl he could growl we could growl you could growl they could growl	I could be growling you could be growling he could be growling we could be growling you could be growling they could be growling
Perfect	V-ing perfect
I could have growled you could have growled he could have growled we could have growled you could have growled they could have growled	I could have been growling you could have been growling he could have been growling we could have been growling you could have been growling they could have been growling

Negation

Simple form	V-ing form
I could not growl you could not growl he could not growl we could not growl you could not growl they could not growl	I could not be growling you could not be growling he could not be growling we could not be growling you could not be growling they could not be growling
Perfect	V-ing perfect
I could not have growled you could not have growled he could not have growled we could not have growled you could not have growled they could not have growled	I could not have been growling you could not have been growling he could not have been growling we could not have been growling you could not have been growling they could not have been growling

Interrogative form

Simple form	V-ing form
could I growl? could you growl? could he growl? could we growl? could you growl? could they growl?	could I be growling? could you be growling? could he be growling? could we be growling? could you be growling? could they be growling?
Perfect	V-ing perfect
could I have growled? could you have growled? could he have growled? could we have growled? could you have growled? could they have growled?	could I have been growling? could you have been growling? could he have been growling? could we have been growling? could you have been growling? could they have been growling?

Interro-negative form

Simple form	V-ing form
could I not growl? could you not growl? could he not growl? could we not growl? could you not growl? could they not growl?	could I not be growling? could you not be growling? could he not be growling? could we not be growling? could you not be growling? could they not be growling?
Perfect	V-ing perfect
could I not have growled? could you not have growled? could he not have growled? could we not have growled? could you not have growled? could they not have growled?	could I not have been growling? could you not have been growling? could he not have been growling? could we not have been growling? could you not have been growling? could they not have been growling?