
Regular verb: borrow - borrowed - borrowed
Simple form | V-ing form | 
| I must borrow you must borrow she must borrow we must borrow you must borrow they must borrow  | 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 | V-ing 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  | 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  | 
Simple form | V-ing form | 
| I mustn't borrow you mustn't borrow she mustn't borrow we mustn't borrow you mustn't borrow they mustn't borrow  | I mustn't be borrowing you mustn't be borrowing she mustn't be borrowing we mustn't be borrowing you mustn't be borrowing they mustn't be borrowing  | 
Perfect | V-ing perfect | 
| I mustn't have borrowed you mustn't have borrowed she mustn't have borrowed we mustn't have borrowed you mustn't have borrowed they mustn't have borrowed  | I mustn't have been borrowing you mustn't have been borrowing she mustn't have been borrowing we mustn't have been borrowing you mustn't have been borrowing they mustn't have been borrowing  | 
Simple form | V-ing form | 
| must I borrow? must you borrow? must she borrow? must we borrow? must you borrow? must they borrow?  | 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 | V-ing 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?  | 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?  | 
Simple form | V-ing form | 
| mustn't I borrow? mustn't you borrow? mustn't she borrow? mustn't we borrow? mustn't you borrow? mustn't they borrow?  | mustn't I be borrowing? mustn't you be borrowing? mustn't she be borrowing? mustn't we be borrowing? mustn't you be borrowing? mustn't they be borrowing?  | 
Perfect | V-ing perfect | 
| mustn't I have borrowed? mustn't you have borrowed? mustn't she have borrowed? mustn't we have borrowed? mustn't you have borrowed? mustn't they have borrowed?  | mustn't I have been borrowing? mustn't you have been borrowing? mustn't she have been borrowing? mustn't we have been borrowing? mustn't you have been borrowing? mustn't they have been borrowing?  |