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