must do
Irregular verb: do - did- done

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must do
you must do
she must do
we must do
you must do
they must do 	I must be doing
you must be doing
she must be doing
we must be doing
you must be doing
they must be doing	I must have done
you must have done
she must have done
we must have done
you must have done
they must have done	I must have been doing
you must have been doing
she must have been doing
we must have been doing
you must have been doing
they must have been doing	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I mustn't do
you mustn't do
she mustn't do
we mustn't do
you mustn't do
they mustn't do 	I mustn't be doing
you mustn't be doing
she mustn't be doing
we mustn't be doing
you mustn't be doing
they mustn't be doing	I mustn't have done
you mustn't have done
she mustn't have done
we mustn't have done
you mustn't have done
they mustn't have done	I mustn't have been doing
you mustn't have been doing
she mustn't have been doing
we mustn't have been doing
you mustn't have been doing
they mustn't have been doing	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I do?
must you do?
must she do?
must we do?
must you do?
must they do? 	must I be doing?
must you be doing?
must she be doing?
must we be doing?
must you be doing?
must they be doing? 	must I have done?
must you have done?
must she have done?
must we have done?
must you have done?
must they have done? 	must I have been doing?
must you have been doing?
must she have been doing?
must we have been doing?
must you have been doing?
must they have been doing? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
mustn't I do?
mustn't you do?
mustn't she do?
mustn't we do?
mustn't you do?
mustn't they do? 	mustn't I be doing?
mustn't you be doing?
mustn't she be doing?
mustn't we be doing?
mustn't you be doing?
mustn't they be doing? 	mustn't I have done?
mustn't you have done?
mustn't she have done?
mustn't we have done?
mustn't you have done?
mustn't they have done? 	mustn't I have been doing?
mustn't you have been doing?
mustn't she have been doing?
mustn't we have been doing?
mustn't you have been doing?
mustn't they have been doing?