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