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