I could remain you could remain he could remain we could remain you could remain they could remain
V-ing form
I could be remaining you could be remaining he could be remaining we could be remaining you could be remaining they could be remaining
Perfect
I could have remained you could have remained he could have remained we could have remained you could have remained they could have remained
V-ing perfect
I could have been remaining you could have been remaining he could have been remaining we could have been remaining you could have been remaining they could have been remaining
Negation
Simple form
I could not remain you could not remain he could not remain we could not remain you could not remain they could not remain
V-ing form
I could not be remaining you could not be remaining he could not be remaining we could not be remaining you could not be remaining they could not be remaining
Perfect
I could not have remained you could not have remained he could not have remained we could not have remained you could not have remained they could not have remained
V-ing perfect
I could not have been remaining you could not have been remaining he could not have been remaining we could not have been remaining you could not have been remaining they could not have been remaining
Interrogative form
Simple form
could I remain? could you remain? could he remain? could we remain? could you remain? could they remain?
V-ing form
could I be remaining? could you be remaining? could he be remaining? could we be remaining? could you be remaining? could they be remaining?
Perfect
could I have remained? could you have remained? could he have remained? could we have remained? could you have remained? could they have remained?
V-ing perfect
could I have been remaining? could you have been remaining? could he have been remaining? could we have been remaining? could you have been remaining? could they have been remaining?
Interro-negative form
Simple form
could I not remain? could you not remain? could he not remain? could we not remain? could you not remain? could they not remain?
V-ing form
could I not be remaining? could you not be remaining? could he not be remaining? could we not be remaining? could you not be remaining? could they not be remaining?
Perfect
could I not have remained? could you not have remained? could he not have remained? could we not have remained? could you not have remained? could they not have remained?
V-ing perfect
could I not have been remaining? could you not have been remaining? could he not have been remaining? could we not have been remaining? could you not have been remaining? could they not have been remaining?