I could bracket you could bracket he could bracket we could bracket you could bracket they could bracket
V-ing form
I could be bracketing you could be bracketing he could be bracketing we could be bracketing you could be bracketing they could be bracketing
Perfect
I could have bracketed you could have bracketed he could have bracketed we could have bracketed you could have bracketed they could have bracketed
V-ing perfect
I could have been bracketing you could have been bracketing he could have been bracketing we could have been bracketing you could have been bracketing they could have been bracketing
Negation
Simple form
I couldn't bracket you couldn't bracket he couldn't bracket we couldn't bracket you couldn't bracket they couldn't bracket
V-ing form
I couldn't be bracketing you couldn't be bracketing he couldn't be bracketing we couldn't be bracketing you couldn't be bracketing they couldn't be bracketing
Perfect
I couldn't have bracketed you couldn't have bracketed he couldn't have bracketed we couldn't have bracketed you couldn't have bracketed they couldn't have bracketed
V-ing perfect
I couldn't have been bracketing you couldn't have been bracketing he couldn't have been bracketing we couldn't have been bracketing you couldn't have been bracketing they couldn't have been bracketing
Interrogative form
Simple form
could I bracket? could you bracket? could he bracket? could we bracket? could you bracket? could they bracket?
V-ing form
could I be bracketing? could you be bracketing? could he be bracketing? could we be bracketing? could you be bracketing? could they be bracketing?
Perfect
could I have bracketed? could you have bracketed? could he have bracketed? could we have bracketed? could you have bracketed? could they have bracketed?
V-ing perfect
could I have been bracketing? could you have been bracketing? could he have been bracketing? could we have been bracketing? could you have been bracketing? could they have been bracketing?
Interro-negative form
Simple form
couldn't I bracket? couldn't you bracket? couldn't he bracket? couldn't we bracket? couldn't you bracket? couldn't they bracket?
V-ing form
couldn't I be bracketing? couldn't you be bracketing? couldn't he be bracketing? couldn't we be bracketing? couldn't you be bracketing? couldn't they be bracketing?
Perfect
couldn't I have bracketed? couldn't you have bracketed? couldn't he have bracketed? couldn't we have bracketed? couldn't you have bracketed? couldn't they have bracketed?
V-ing perfect
couldn't I have been bracketing? couldn't you have been bracketing? couldn't he have been bracketing? couldn't we have been bracketing? couldn't you have been bracketing? couldn't they have been bracketing?