I can allow you can allow he can allow we can allow you can allow they can allow
V-ing form
I can be allowing you can be allowing he can be allowing we can be allowing you can be allowing they can be allowing
Perfect
I can have allowed you can have allowed he can have allowed we can have allowed you can have allowed they can have allowed
V-ing perfect
I can have been allowing you can have been allowing he can have been allowing we can have been allowing you can have been allowing they can have been allowing
Negation
Simple form
I cannot allow you cannot allow he cannot allow we cannot allow you cannot allow they cannot allow
V-ing form
I cannot be allowing you cannot be allowing he cannot be allowing we cannot be allowing you cannot be allowing they cannot be allowing
Perfect
I cannot have allowed you cannot have allowed he cannot have allowed we cannot have allowed you cannot have allowed they cannot have allowed
V-ing perfect
I cannot have been allowing you cannot have been allowing he cannot have been allowing we cannot have been allowing you cannot have been allowing they cannot have been allowing
Interrogative form
Simple form
can I allow? can you allow? can he allow? can we allow? can you allow? can they allow?
V-ing form
can I be allowing? can you be allowing? can he be allowing? can we be allowing? can you be allowing? can they be allowing?
Perfect
can I have allowed? can you have allowed? can he have allowed? can we have allowed? can you have allowed? can they have allowed?
V-ing perfect
can I have been allowing? can you have been allowing? can he have been allowing? can we have been allowing? can you have been allowing? can they have been allowing?
Interro-negative form
Simple form
can I not allow? can you not allow? can he not allow? can we not allow? can you not allow? can they not allow?
V-ing form
can I not be allowing? can you not be allowing? can he not be allowing? can we not be allowing? can you not be allowing? can they not be allowing?
Perfect
can I not have allowed? can you not have allowed? can he not have allowed? can we not have allowed? can you not have allowed? can they not have allowed?
V-ing perfect
can I not have been allowing? can you not have been allowing? can he not have been allowing? can we not have been allowing? can you not have been allowing? can they not have been allowing?