English verb conjugation
COULD COLLAPSE

Regular verb: collapse - collapsed - collapsed

Affirmation

Simple form	V-ing form
I could collapse you could collapse she could collapse we could collapse you could collapse they could collapse	I could be collapsing you could be collapsing she could be collapsing we could be collapsing you could be collapsing they could be collapsing
Perfect	V-ing perfect
I could have collapsed you could have collapsed she could have collapsed we could have collapsed you could have collapsed they could have collapsed	I could have been collapsing you could have been collapsing she could have been collapsing we could have been collapsing you could have been collapsing they could have been collapsing

Negation

Simple form	V-ing form
I could not collapse you could not collapse she could not collapse we could not collapse you could not collapse they could not collapse	I could not be collapsing you could not be collapsing she could not be collapsing we could not be collapsing you could not be collapsing they could not be collapsing
Perfect	V-ing perfect
I could not have collapsed you could not have collapsed she could not have collapsed we could not have collapsed you could not have collapsed they could not have collapsed	I could not have been collapsing you could not have been collapsing she could not have been collapsing we could not have been collapsing you could not have been collapsing they could not have been collapsing

Interrogative form

Simple form	V-ing form
could I collapse? could you collapse? could she collapse? could we collapse? could you collapse? could they collapse?	could I be collapsing? could you be collapsing? could she be collapsing? could we be collapsing? could you be collapsing? could they be collapsing?
Perfect	V-ing perfect
could I have collapsed? could you have collapsed? could she have collapsed? could we have collapsed? could you have collapsed? could they have collapsed?	could I have been collapsing? could you have been collapsing? could she have been collapsing? could we have been collapsing? could you have been collapsing? could they have been collapsing?

Interro-negative form

Simple form	V-ing form
could I not collapse? could you not collapse? could she not collapse? could we not collapse? could you not collapse? could they not collapse?	could I not be collapsing? could you not be collapsing? could she not be collapsing? could we not be collapsing? could you not be collapsing? could they not be collapsing?
Perfect	V-ing perfect
could I not have collapsed? could you not have collapsed? could she not have collapsed? could we not have collapsed? could you not have collapsed? could they not have collapsed?	could I not have been collapsing? could you not have been collapsing? could she not have been collapsing? could we not have been collapsing? could you not have been collapsing? could they not have been collapsing?