I can treat you can treat she can treat we can treat you can treat they can treat
V-ing form
I can be treating you can be treating she can be treating we can be treating you can be treating they can be treating
Perfect
I can have treated you can have treated she can have treated we can have treated you can have treated they can have treated
V-ing perfect
I can have been treating you can have been treating she can have been treating we can have been treating you can have been treating they can have been treating
Negation
Simple form
I can't treat you can't treat she can't treat we can't treat you can't treat they can't treat
V-ing form
I can't be treating you can't be treating she can't be treating we can't be treating you can't be treating they can't be treating
Perfect
I can't have treated you can't have treated she can't have treated we can't have treated you can't have treated they can't have treated
V-ing perfect
I can't have been treating you can't have been treating she can't have been treating we can't have been treating you can't have been treating they can't have been treating
Interrogative form
Simple form
can I treat? can you treat? can she treat? can we treat? can you treat? can they treat?
V-ing form
can I be treating? can you be treating? can she be treating? can we be treating? can you be treating? can they be treating?
Perfect
can I have treated? can you have treated? can she have treated? can we have treated? can you have treated? can they have treated?
V-ing perfect
can I have been treating? can you have been treating? can she have been treating? can we have been treating? can you have been treating? can they have been treating?
Interro-negative form
Simple form
can't I treat? can't you treat? can't she treat? can't we treat? can't you treat? can't they treat?
V-ing form
can't I be treating? can't you be treating? can't she be treating? can't we be treating? can't you be treating? can't they be treating?
Perfect
can't I have treated? can't you have treated? can't she have treated? can't we have treated? can't you have treated? can't they have treated?
V-ing perfect
can't I have been treating? can't you have been treating? can't she have been treating? can't we have been treating? can't you have been treating? can't they have been treating?