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 couldn't remain you couldn't remain he couldn't remain we couldn't remain you couldn't remain they couldn't remain
V-ing form
I couldn't be remaining you couldn't be remaining he couldn't be remaining we couldn't be remaining you couldn't be remaining they couldn't be remaining
Perfect
I couldn't have remained you couldn't have remained he couldn't have remained we couldn't have remained you couldn't have remained they couldn't have remained
V-ing perfect
I couldn't have been remaining you couldn't have been remaining he couldn't have been remaining we couldn't have been remaining you couldn't have been remaining they couldn't 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
couldn't I remain? couldn't you remain? couldn't he remain? couldn't we remain? couldn't you remain? couldn't they remain?
V-ing form
couldn't I be remaining? couldn't you be remaining? couldn't he be remaining? couldn't we be remaining? couldn't you be remaining? couldn't they be remaining?
Perfect
couldn't I have remained? couldn't you have remained? couldn't he have remained? couldn't we have remained? couldn't you have remained? couldn't they have remained?
V-ing perfect
couldn't I have been remaining? couldn't you have been remaining? couldn't he have been remaining? couldn't we have been remaining? couldn't you have been remaining? couldn't they have been remaining?