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