English verb conjugation
CAN ROLLER-SKATE

Regular verb: roller-skate - roller-skated - roller-skated

Affirmation

Simple form	V-ing form
I can roller-skate you can roller-skate he can roller-skate we can roller-skate you can roller-skate they can roller-skate	I can be roller-skating you can be roller-skating he can be roller-skating we can be roller-skating you can be roller-skating they can be roller-skating
Perfect	V-ing perfect
I can have roller-skated you can have roller-skated he can have roller-skated we can have roller-skated you can have roller-skated they can have roller-skated	I can have been roller-skating you can have been roller-skating he can have been roller-skating we can have been roller-skating you can have been roller-skating they can have been roller-skating

Negation

Simple form	V-ing form
I can't roller-skate you can't roller-skate he can't roller-skate we can't roller-skate you can't roller-skate they can't roller-skate	I can't be roller-skating you can't be roller-skating he can't be roller-skating we can't be roller-skating you can't be roller-skating they can't be roller-skating
Perfect	V-ing perfect
I can't have roller-skated you can't have roller-skated he can't have roller-skated we can't have roller-skated you can't have roller-skated they can't have roller-skated	I can't have been roller-skating you can't have been roller-skating he can't have been roller-skating we can't have been roller-skating you can't have been roller-skating they can't have been roller-skating

Interrogative form

Simple form	V-ing form
can I roller-skate? can you roller-skate? can he roller-skate? can we roller-skate? can you roller-skate? can they roller-skate?	can I be roller-skating? can you be roller-skating? can he be roller-skating? can we be roller-skating? can you be roller-skating? can they be roller-skating?
Perfect	V-ing perfect
can I have roller-skated? can you have roller-skated? can he have roller-skated? can we have roller-skated? can you have roller-skated? can they have roller-skated?	can I have been roller-skating? can you have been roller-skating? can he have been roller-skating? can we have been roller-skating? can you have been roller-skating? can they have been roller-skating?

Interro-negative form

Simple form	V-ing form
can't I roller-skate? can't you roller-skate? can't he roller-skate? can't we roller-skate? can't you roller-skate? can't they roller-skate?	can't I be roller-skating? can't you be roller-skating? can't he be roller-skating? can't we be roller-skating? can't you be roller-skating? can't they be roller-skating?
Perfect	V-ing perfect
can't I have roller-skated? can't you have roller-skated? can't he have roller-skated? can't we have roller-skated? can't you have roller-skated? can't they have roller-skated?	can't I have been roller-skating? can't you have been roller-skating? can't he have been roller-skating? can't we have been roller-skating? can't you have been roller-skating? can't they have been roller-skating?