I can maintain you can maintain he can maintain we can maintain you can maintain they can maintain
V-ing form
I can be maintaining you can be maintaining he can be maintaining we can be maintaining you can be maintaining they can be maintaining
Perfect
I can have maintained you can have maintained he can have maintained we can have maintained you can have maintained they can have maintained
V-ing perfect
I can have been maintaining you can have been maintaining he can have been maintaining we can have been maintaining you can have been maintaining they can have been maintaining
Negation
Simple form
I can't maintain you can't maintain he can't maintain we can't maintain you can't maintain they can't maintain
V-ing form
I can't be maintaining you can't be maintaining he can't be maintaining we can't be maintaining you can't be maintaining they can't be maintaining
Perfect
I can't have maintained you can't have maintained he can't have maintained we can't have maintained you can't have maintained they can't have maintained
V-ing perfect
I can't have been maintaining you can't have been maintaining he can't have been maintaining we can't have been maintaining you can't have been maintaining they can't have been maintaining
Interrogative form
Simple form
can I maintain? can you maintain? can he maintain? can we maintain? can you maintain? can they maintain?
V-ing form
can I be maintaining? can you be maintaining? can he be maintaining? can we be maintaining? can you be maintaining? can they be maintaining?
Perfect
can I have maintained? can you have maintained? can he have maintained? can we have maintained? can you have maintained? can they have maintained?
V-ing perfect
can I have been maintaining? can you have been maintaining? can he have been maintaining? can we have been maintaining? can you have been maintaining? can they have been maintaining?
Interro-negative form
Simple form
can't I maintain? can't you maintain? can't he maintain? can't we maintain? can't you maintain? can't they maintain?
V-ing form
can't I be maintaining? can't you be maintaining? can't he be maintaining? can't we be maintaining? can't you be maintaining? can't they be maintaining?
Perfect
can't I have maintained? can't you have maintained? can't he have maintained? can't we have maintained? can't you have maintained? can't they have maintained?
V-ing perfect
can't I have been maintaining? can't you have been maintaining? can't he have been maintaining? can't we have been maintaining? can't you have been maintaining? can't they have been maintaining?