I must balance you must balance she must balance we must balance you must balance they must balance
V-ing form
I must be balancing you must be balancing she must be balancing we must be balancing you must be balancing they must be balancing
Perfect
I must have balanced you must have balanced she must have balanced we must have balanced you must have balanced they must have balanced
V-ing perfect
I must have been balancing you must have been balancing she must have been balancing we must have been balancing you must have been balancing they must have been balancing
Negation
Simple form
I mustn't balance you mustn't balance she mustn't balance we mustn't balance you mustn't balance they mustn't balance
V-ing form
I mustn't be balancing you mustn't be balancing she mustn't be balancing we mustn't be balancing you mustn't be balancing they mustn't be balancing
Perfect
I mustn't have balanced you mustn't have balanced she mustn't have balanced we mustn't have balanced you mustn't have balanced they mustn't have balanced
V-ing perfect
I mustn't have been balancing you mustn't have been balancing she mustn't have been balancing we mustn't have been balancing you mustn't have been balancing they mustn't have been balancing
Interrogative form
Simple form
must I balance? must you balance? must she balance? must we balance? must you balance? must they balance?
V-ing form
must I be balancing? must you be balancing? must she be balancing? must we be balancing? must you be balancing? must they be balancing?
Perfect
must I have balanced? must you have balanced? must she have balanced? must we have balanced? must you have balanced? must they have balanced?
V-ing perfect
must I have been balancing? must you have been balancing? must she have been balancing? must we have been balancing? must you have been balancing? must they have been balancing?
Interro-negative form
Simple form
mustn't I balance? mustn't you balance? mustn't she balance? mustn't we balance? mustn't you balance? mustn't they balance?
V-ing form
mustn't I be balancing? mustn't you be balancing? mustn't she be balancing? mustn't we be balancing? mustn't you be balancing? mustn't they be balancing?
Perfect
mustn't I have balanced? mustn't you have balanced? mustn't she have balanced? mustn't we have balanced? mustn't you have balanced? mustn't they have balanced?
V-ing perfect
mustn't I have been balancing? mustn't you have been balancing? mustn't she have been balancing? mustn't we have been balancing? mustn't you have been balancing? mustn't they have been balancing?