I could superscribe you could superscribe he could superscribe we could superscribe you could superscribe they could superscribe
V-ing form
I could be superscribing you could be superscribing he could be superscribing we could be superscribing you could be superscribing they could be superscribing
Perfect
I could have superscribed you could have superscribed he could have superscribed we could have superscribed you could have superscribed they could have superscribed
V-ing perfect
I could have been superscribing you could have been superscribing he could have been superscribing we could have been superscribing you could have been superscribing they could have been superscribing
Negation
Simple form
I could not superscribe you could not superscribe he could not superscribe we could not superscribe you could not superscribe they could not superscribe
V-ing form
I could not be superscribing you could not be superscribing he could not be superscribing we could not be superscribing you could not be superscribing they could not be superscribing
Perfect
I could not have superscribed you could not have superscribed he could not have superscribed we could not have superscribed you could not have superscribed they could not have superscribed
V-ing perfect
I could not have been superscribing you could not have been superscribing he could not have been superscribing we could not have been superscribing you could not have been superscribing they could not have been superscribing
Interrogative form
Simple form
could I superscribe? could you superscribe? could he superscribe? could we superscribe? could you superscribe? could they superscribe?
V-ing form
could I be superscribing? could you be superscribing? could he be superscribing? could we be superscribing? could you be superscribing? could they be superscribing?
Perfect
could I have superscribed? could you have superscribed? could he have superscribed? could we have superscribed? could you have superscribed? could they have superscribed?
V-ing perfect
could I have been superscribing? could you have been superscribing? could he have been superscribing? could we have been superscribing? could you have been superscribing? could they have been superscribing?
Interro-negative form
Simple form
could I not superscribe? could you not superscribe? could he not superscribe? could we not superscribe? could you not superscribe? could they not superscribe?
V-ing form
could I not be superscribing? could you not be superscribing? could he not be superscribing? could we not be superscribing? could you not be superscribing? could they not be superscribing?
Perfect
could I not have superscribed? could you not have superscribed? could he not have superscribed? could we not have superscribed? could you not have superscribed? could they not have superscribed?
V-ing perfect
could I not have been superscribing? could you not have been superscribing? could he not have been superscribing? could we not have been superscribing? could you not have been superscribing? could they not have been superscribing?