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 cannot roller-skate you cannot roller-skate he cannot roller-skate we cannot roller-skate you cannot roller-skate they cannot roller-skate	I cannot be roller-skating you cannot be roller-skating he cannot be roller-skating we cannot be roller-skating you cannot be roller-skating they cannot be roller-skating
Perfect	V-ing perfect
I cannot have roller-skated you cannot have roller-skated he cannot have roller-skated we cannot have roller-skated you cannot have roller-skated they cannot have roller-skated	I cannot have been roller-skating you cannot have been roller-skating he cannot have been roller-skating we cannot have been roller-skating you cannot have been roller-skating they cannot 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 I not roller-skate? can you not roller-skate? can he not roller-skate? can we not roller-skate? can you not roller-skate? can they not roller-skate?	can I not be roller-skating? can you not be roller-skating? can he not be roller-skating? can we not be roller-skating? can you not be roller-skating? can they not be roller-skating?
Perfect	V-ing perfect
can I not have roller-skated? can you not have roller-skated? can he not have roller-skated? can we not have roller-skated? can you not have roller-skated? can they not have roller-skated?	can I not have been roller-skating? can you not have been roller-skating? can he not have been roller-skating? can we not have been roller-skating? can you not have been roller-skating? can they not have been roller-skating?