I can close you can close he can close we can close you can close they can close
V-ing form
I can be closing you can be closing he can be closing we can be closing you can be closing they can be closing
Perfect
I can have closed you can have closed he can have closed we can have closed you can have closed they can have closed
V-ing perfect
I can have been closing you can have been closing he can have been closing we can have been closing you can have been closing they can have been closing
Negation
Simple form
I cannot close you cannot close he cannot close we cannot close you cannot close they cannot close
V-ing form
I cannot be closing you cannot be closing he cannot be closing we cannot be closing you cannot be closing they cannot be closing
Perfect
I cannot have closed you cannot have closed he cannot have closed we cannot have closed you cannot have closed they cannot have closed
V-ing perfect
I cannot have been closing you cannot have been closing he cannot have been closing we cannot have been closing you cannot have been closing they cannot have been closing
Interrogative form
Simple form
can I close? can you close? can he close? can we close? can you close? can they close?
V-ing form
can I be closing? can you be closing? can he be closing? can we be closing? can you be closing? can they be closing?
Perfect
can I have closed? can you have closed? can he have closed? can we have closed? can you have closed? can they have closed?
V-ing perfect
can I have been closing? can you have been closing? can he have been closing? can we have been closing? can you have been closing? can they have been closing?
Interro-negative form
Simple form
can I not close? can you not close? can he not close? can we not close? can you not close? can they not close?
V-ing form
can I not be closing? can you not be closing? can he not be closing? can we not be closing? can you not be closing? can they not be closing?
Perfect
can I not have closed? can you not have closed? can he not have closed? can we not have closed? can you not have closed? can they not have closed?
V-ing perfect
can I not have been closing? can you not have been closing? can he not have been closing? can we not have been closing? can you not have been closing? can they not have been closing?