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