I can leather you can leather he can leather we can leather you can leather they can leather
V-ing form
I can be leathering you can be leathering he can be leathering we can be leathering you can be leathering they can be leathering
Perfect
I can have leathered you can have leathered he can have leathered we can have leathered you can have leathered they can have leathered
V-ing perfect
I can have been leathering you can have been leathering he can have been leathering we can have been leathering you can have been leathering they can have been leathering
Negation
Simple form
I can't leather you can't leather he can't leather we can't leather you can't leather they can't leather
V-ing form
I can't be leathering you can't be leathering he can't be leathering we can't be leathering you can't be leathering they can't be leathering
Perfect
I can't have leathered you can't have leathered he can't have leathered we can't have leathered you can't have leathered they can't have leathered
V-ing perfect
I can't have been leathering you can't have been leathering he can't have been leathering we can't have been leathering you can't have been leathering they can't have been leathering
Interrogative form
Simple form
can I leather? can you leather? can he leather? can we leather? can you leather? can they leather?
V-ing form
can I be leathering? can you be leathering? can he be leathering? can we be leathering? can you be leathering? can they be leathering?
Perfect
can I have leathered? can you have leathered? can he have leathered? can we have leathered? can you have leathered? can they have leathered?
V-ing perfect
can I have been leathering? can you have been leathering? can he have been leathering? can we have been leathering? can you have been leathering? can they have been leathering?
Interro-negative form
Simple form
can't I leather? can't you leather? can't he leather? can't we leather? can't you leather? can't they leather?
V-ing form
can't I be leathering? can't you be leathering? can't he be leathering? can't we be leathering? can't you be leathering? can't they be leathering?
Perfect
can't I have leathered? can't you have leathered? can't he have leathered? can't we have leathered? can't you have leathered? can't they have leathered?
V-ing perfect
can't I have been leathering? can't you have been leathering? can't he have been leathering? can't we have been leathering? can't you have been leathering? can't they have been leathering?