English verb conjugation
CAN RACK

Regular verb: rack - racked - racked

Affirmation

Simple form	V-ing form
I can rack you can rack he can rack we can rack you can rack they can rack	I can be racking you can be racking he can be racking we can be racking you can be racking they can be racking
Perfect	V-ing perfect
I can have racked you can have racked he can have racked we can have racked you can have racked they can have racked	I can have been racking you can have been racking he can have been racking we can have been racking you can have been racking they can have been racking

Negation

Simple form	V-ing form
I can't rack you can't rack he can't rack we can't rack you can't rack they can't rack	I can't be racking you can't be racking he can't be racking we can't be racking you can't be racking they can't be racking
Perfect	V-ing perfect
I can't have racked you can't have racked he can't have racked we can't have racked you can't have racked they can't have racked	I can't have been racking you can't have been racking he can't have been racking we can't have been racking you can't have been racking they can't have been racking

Interrogative form

Simple form	V-ing form
can I rack? can you rack? can he rack? can we rack? can you rack? can they rack?	can I be racking? can you be racking? can he be racking? can we be racking? can you be racking? can they be racking?
Perfect	V-ing perfect
can I have racked? can you have racked? can he have racked? can we have racked? can you have racked? can they have racked?	can I have been racking? can you have been racking? can he have been racking? can we have been racking? can you have been racking? can they have been racking?

Interro-negative form

Simple form	V-ing form
can't I rack? can't you rack? can't he rack? can't we rack? can't you rack? can't they rack?	can't I be racking? can't you be racking? can't he be racking? can't we be racking? can't you be racking? can't they be racking?
Perfect	V-ing perfect
can't I have racked? can't you have racked? can't he have racked? can't we have racked? can't you have racked? can't they have racked?	can't I have been racking? can't you have been racking? can't he have been racking? can't we have been racking? can't you have been racking? can't they have been racking?