I must borrow you must borrow she must borrow we must borrow you must borrow they must borrow
V-ing form
I must be borrowing you must be borrowing she must be borrowing we must be borrowing you must be borrowing they must be borrowing
Perfect
I must have borrowed you must have borrowed she must have borrowed we must have borrowed you must have borrowed they must have borrowed
V-ing perfect
I must have been borrowing you must have been borrowing she must have been borrowing we must have been borrowing you must have been borrowing they must have been borrowing
Negation
Simple form
I must not borrow you must not borrow she must not borrow we must not borrow you must not borrow they must not borrow
V-ing form
I must not be borrowing you must not be borrowing she must not be borrowing we must not be borrowing you must not be borrowing they must not be borrowing
Perfect
I must not have borrowed you must not have borrowed she must not have borrowed we must not have borrowed you must not have borrowed they must not have borrowed
V-ing perfect
I must not have been borrowing you must not have been borrowing she must not have been borrowing we must not have been borrowing you must not have been borrowing they must not have been borrowing
Interrogative form
Simple form
must I borrow? must you borrow? must she borrow? must we borrow? must you borrow? must they borrow?
V-ing form
must I be borrowing? must you be borrowing? must she be borrowing? must we be borrowing? must you be borrowing? must they be borrowing?
Perfect
must I have borrowed? must you have borrowed? must she have borrowed? must we have borrowed? must you have borrowed? must they have borrowed?
V-ing perfect
must I have been borrowing? must you have been borrowing? must she have been borrowing? must we have been borrowing? must you have been borrowing? must they have been borrowing?
Interro-negative form
Simple form
must I not borrow? must you not borrow? must she not borrow? must we not borrow? must you not borrow? must they not borrow?
V-ing form
must I not be borrowing? must you not be borrowing? must she not be borrowing? must we not be borrowing? must you not be borrowing? must they not be borrowing?
Perfect
must I not have borrowed? must you not have borrowed? must she not have borrowed? must we not have borrowed? must you not have borrowed? must they not have borrowed?
V-ing perfect
must I not have been borrowing? must you not have been borrowing? must she not have been borrowing? must we not have been borrowing? must you not have been borrowing? must they not have been borrowing?