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