I can seat you can seat he can seat we can seat you can seat they can seat
V-ing form
I can be seating you can be seating he can be seating we can be seating you can be seating they can be seating
Perfect
I can have seated you can have seated he can have seated we can have seated you can have seated they can have seated
V-ing perfect
I can have been seating you can have been seating he can have been seating we can have been seating you can have been seating they can have been seating
Negation
Simple form
I cannot seat you cannot seat he cannot seat we cannot seat you cannot seat they cannot seat
V-ing form
I cannot be seating you cannot be seating he cannot be seating we cannot be seating you cannot be seating they cannot be seating
Perfect
I cannot have seated you cannot have seated he cannot have seated we cannot have seated you cannot have seated they cannot have seated
V-ing perfect
I cannot have been seating you cannot have been seating he cannot have been seating we cannot have been seating you cannot have been seating they cannot have been seating
Interrogative form
Simple form
can I seat? can you seat? can he seat? can we seat? can you seat? can they seat?
V-ing form
can I be seating? can you be seating? can he be seating? can we be seating? can you be seating? can they be seating?
Perfect
can I have seated? can you have seated? can he have seated? can we have seated? can you have seated? can they have seated?
V-ing perfect
can I have been seating? can you have been seating? can he have been seating? can we have been seating? can you have been seating? can they have been seating?
Interro-negative form
Simple form
can I not seat? can you not seat? can he not seat? can we not seat? can you not seat? can they not seat?
V-ing form
can I not be seating? can you not be seating? can he not be seating? can we not be seating? can you not be seating? can they not be seating?
Perfect
can I not have seated? can you not have seated? can he not have seated? can we not have seated? can you not have seated? can they not have seated?
V-ing perfect
can I not have been seating? can you not have been seating? can he not have been seating? can we not have been seating? can you not have been seating? can they not have been seating?