I could prescribe you could prescribe he could prescribe we could prescribe you could prescribe they could prescribe
V-ing form
I could be prescribing you could be prescribing he could be prescribing we could be prescribing you could be prescribing they could be prescribing
Perfect
I could have prescribed you could have prescribed he could have prescribed we could have prescribed you could have prescribed they could have prescribed
V-ing perfect
I could have been prescribing you could have been prescribing he could have been prescribing we could have been prescribing you could have been prescribing they could have been prescribing
Negation
Simple form
I could not prescribe you could not prescribe he could not prescribe we could not prescribe you could not prescribe they could not prescribe
V-ing form
I could not be prescribing you could not be prescribing he could not be prescribing we could not be prescribing you could not be prescribing they could not be prescribing
Perfect
I could not have prescribed you could not have prescribed he could not have prescribed we could not have prescribed you could not have prescribed they could not have prescribed
V-ing perfect
I could not have been prescribing you could not have been prescribing he could not have been prescribing we could not have been prescribing you could not have been prescribing they could not have been prescribing
Interrogative form
Simple form
could I prescribe? could you prescribe? could he prescribe? could we prescribe? could you prescribe? could they prescribe?
V-ing form
could I be prescribing? could you be prescribing? could he be prescribing? could we be prescribing? could you be prescribing? could they be prescribing?
Perfect
could I have prescribed? could you have prescribed? could he have prescribed? could we have prescribed? could you have prescribed? could they have prescribed?
V-ing perfect
could I have been prescribing? could you have been prescribing? could he have been prescribing? could we have been prescribing? could you have been prescribing? could they have been prescribing?
Interro-negative form
Simple form
could I not prescribe? could you not prescribe? could he not prescribe? could we not prescribe? could you not prescribe? could they not prescribe?
V-ing form
could I not be prescribing? could you not be prescribing? could he not be prescribing? could we not be prescribing? could you not be prescribing? could they not be prescribing?
Perfect
could I not have prescribed? could you not have prescribed? could he not have prescribed? could we not have prescribed? could you not have prescribed? could they not have prescribed?
V-ing perfect
could I not have been prescribing? could you not have been prescribing? could he not have been prescribing? could we not have been prescribing? could you not have been prescribing? could they not have been prescribing?