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 can't close you can't close he can't close we can't close you can't close they can't close
V-ing form
I can't be closing you can't be closing he can't be closing we can't be closing you can't be closing they can't be closing
Perfect
I can't have closed you can't have closed he can't have closed we can't have closed you can't have closed they can't have closed
V-ing perfect
I can't have been closing you can't have been closing he can't have been closing we can't have been closing you can't have been closing they can't 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't I close? can't you close? can't he close? can't we close? can't you close? can't they close?
V-ing form
can't I be closing? can't you be closing? can't he be closing? can't we be closing? can't you be closing? can't they be closing?
Perfect
can't I have closed? can't you have closed? can't he have closed? can't we have closed? can't you have closed? can't they have closed?
V-ing perfect
can't I have been closing? can't you have been closing? can't he have been closing? can't we have been closing? can't you have been closing? can't they have been closing?