English verb conjugation
CAN COLLAPSE

Regular verb: collapse - collapsed - collapsed

Affirmation

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

Negation

Simple form	V-ing form
I can't collapse you can't collapse he can't collapse we can't collapse you can't collapse they can't collapse	I can't be collapsing you can't be collapsing he can't be collapsing we can't be collapsing you can't be collapsing they can't be collapsing
Perfect	V-ing perfect
I can't have collapsed you can't have collapsed he can't have collapsed we can't have collapsed you can't have collapsed they can't have collapsed	I can't have been collapsing you can't have been collapsing he can't have been collapsing we can't have been collapsing you can't have been collapsing they can't have been collapsing

Interrogative form

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

Interro-negative form

Simple form	V-ing form
can't I collapse? can't you collapse? can't he collapse? can't we collapse? can't you collapse? can't they collapse?	can't I be collapsing? can't you be collapsing? can't he be collapsing? can't we be collapsing? can't you be collapsing? can't they be collapsing?
Perfect	V-ing perfect
can't I have collapsed? can't you have collapsed? can't he have collapsed? can't we have collapsed? can't you have collapsed? can't they have collapsed?	can't I have been collapsing? can't you have been collapsing? can't he have been collapsing? can't we have been collapsing? can't you have been collapsing? can't they have been collapsing?