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