English verb conjugation
COULD CHIRRUP

Regular verb: chirrup - chirruped - chirruped

Affirmation

Simple form	V-ing form
I could chirrup you could chirrup he could chirrup we could chirrup you could chirrup they could chirrup	I could be chirruping you could be chirruping he could be chirruping we could be chirruping you could be chirruping they could be chirruping
Perfect	V-ing perfect
I could have chirruped you could have chirruped he could have chirruped we could have chirruped you could have chirruped they could have chirruped	I could have been chirruping you could have been chirruping he could have been chirruping we could have been chirruping you could have been chirruping they could have been chirruping

Negation

Simple form	V-ing form
I could not chirrup you could not chirrup he could not chirrup we could not chirrup you could not chirrup they could not chirrup	I could not be chirruping you could not be chirruping he could not be chirruping we could not be chirruping you could not be chirruping they could not be chirruping
Perfect	V-ing perfect
I could not have chirruped you could not have chirruped he could not have chirruped we could not have chirruped you could not have chirruped they could not have chirruped	I could not have been chirruping you could not have been chirruping he could not have been chirruping we could not have been chirruping you could not have been chirruping they could not have been chirruping

Interrogative form

Simple form	V-ing form
could I chirrup? could you chirrup? could he chirrup? could we chirrup? could you chirrup? could they chirrup?	could I be chirruping? could you be chirruping? could he be chirruping? could we be chirruping? could you be chirruping? could they be chirruping?
Perfect	V-ing perfect
could I have chirruped? could you have chirruped? could he have chirruped? could we have chirruped? could you have chirruped? could they have chirruped?	could I have been chirruping? could you have been chirruping? could he have been chirruping? could we have been chirruping? could you have been chirruping? could they have been chirruping?

Interro-negative form

Simple form	V-ing form
could I not chirrup? could you not chirrup? could he not chirrup? could we not chirrup? could you not chirrup? could they not chirrup?	could I not be chirruping? could you not be chirruping? could he not be chirruping? could we not be chirruping? could you not be chirruping? could they not be chirruping?
Perfect	V-ing perfect
could I not have chirruped? could you not have chirruped? could he not have chirruped? could we not have chirruped? could you not have chirruped? could they not have chirruped?	could I not have been chirruping? could you not have been chirruping? could he not have been chirruping? could we not have been chirruping? could you not have been chirruping? could they not have been chirruping?