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