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