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