English verb conjugation
COULD YOWL

Regular verb: yowl - yowled - yowled

Affirmation

Simple form	V-ing form
I could yowl you could yowl he could yowl we could yowl you could yowl they could yowl	I could be yowling you could be yowling he could be yowling we could be yowling you could be yowling they could be yowling
Perfect	V-ing perfect
I could have yowled you could have yowled he could have yowled we could have yowled you could have yowled they could have yowled	I could have been yowling you could have been yowling he could have been yowling we could have been yowling you could have been yowling they could have been yowling

Negation

Simple form	V-ing form
I could not yowl you could not yowl he could not yowl we could not yowl you could not yowl they could not yowl	I could not be yowling you could not be yowling he could not be yowling we could not be yowling you could not be yowling they could not be yowling
Perfect	V-ing perfect
I could not have yowled you could not have yowled he could not have yowled we could not have yowled you could not have yowled they could not have yowled	I could not have been yowling you could not have been yowling he could not have been yowling we could not have been yowling you could not have been yowling they could not have been yowling

Interrogative form

Simple form	V-ing form
could I yowl? could you yowl? could he yowl? could we yowl? could you yowl? could they yowl?	could I be yowling? could you be yowling? could he be yowling? could we be yowling? could you be yowling? could they be yowling?
Perfect	V-ing perfect
could I have yowled? could you have yowled? could he have yowled? could we have yowled? could you have yowled? could they have yowled?	could I have been yowling? could you have been yowling? could he have been yowling? could we have been yowling? could you have been yowling? could they have been yowling?

Interro-negative form

Simple form	V-ing form
could I not yowl? could you not yowl? could he not yowl? could we not yowl? could you not yowl? could they not yowl?	could I not be yowling? could you not be yowling? could he not be yowling? could we not be yowling? could you not be yowling? could they not be yowling?
Perfect	V-ing perfect
could I not have yowled? could you not have yowled? could he not have yowled? could we not have yowled? could you not have yowled? could they not have yowled?	could I not have been yowling? could you not have been yowling? could he not have been yowling? could we not have been yowling? could you not have been yowling? could they not have been yowling?