English verb conjugation
COULD YAWP

Regular verb: yawp - yawped - yawped

Affirmation

Simple form	V-ing form
I could yawp you could yawp he could yawp we could yawp you could yawp they could yawp	I could be yawping you could be yawping he could be yawping we could be yawping you could be yawping they could be yawping
Perfect	V-ing perfect
I could have yawped you could have yawped he could have yawped we could have yawped you could have yawped they could have yawped	I could have been yawping you could have been yawping he could have been yawping we could have been yawping you could have been yawping they could have been yawping

Negation

Simple form	V-ing form
I couldn't yawp you couldn't yawp he couldn't yawp we couldn't yawp you couldn't yawp they couldn't yawp	I couldn't be yawping you couldn't be yawping he couldn't be yawping we couldn't be yawping you couldn't be yawping they couldn't be yawping
Perfect	V-ing perfect
I couldn't have yawped you couldn't have yawped he couldn't have yawped we couldn't have yawped you couldn't have yawped they couldn't have yawped	I couldn't have been yawping you couldn't have been yawping he couldn't have been yawping we couldn't have been yawping you couldn't have been yawping they couldn't have been yawping

Interrogative form

Simple form	V-ing form
could I yawp? could you yawp? could he yawp? could we yawp? could you yawp? could they yawp?	could I be yawping? could you be yawping? could he be yawping? could we be yawping? could you be yawping? could they be yawping?
Perfect	V-ing perfect
could I have yawped? could you have yawped? could he have yawped? could we have yawped? could you have yawped? could they have yawped?	could I have been yawping? could you have been yawping? could he have been yawping? could we have been yawping? could you have been yawping? could they have been yawping?

Interro-negative form

Simple form	V-ing form
couldn't I yawp? couldn't you yawp? couldn't he yawp? couldn't we yawp? couldn't you yawp? couldn't they yawp?	couldn't I be yawping? couldn't you be yawping? couldn't he be yawping? couldn't we be yawping? couldn't you be yawping? couldn't they be yawping?
Perfect	V-ing perfect
couldn't I have yawped? couldn't you have yawped? couldn't he have yawped? couldn't we have yawped? couldn't you have yawped? couldn't they have yawped?	couldn't I have been yawping? couldn't you have been yawping? couldn't he have been yawping? couldn't we have been yawping? couldn't you have been yawping? couldn't they have been yawping?