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