must dust
Regular verb: dust - dusted- dusted

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must dust
you must dust
she must dust
we must dust
you must dust
they must dust 	I must be dusting
you must be dusting
she must be dusting
we must be dusting
you must be dusting
they must be dusting	I must have dusted
you must have dusted
she must have dusted
we must have dusted
you must have dusted
they must have dusted	I must have been dusting
you must have been dusting
she must have been dusting
we must have been dusting
you must have been dusting
they must have been dusting	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I mustn't dust
you mustn't dust
she mustn't dust
we mustn't dust
you mustn't dust
they mustn't dust 	I mustn't be dusting
you mustn't be dusting
she mustn't be dusting
we mustn't be dusting
you mustn't be dusting
they mustn't be dusting	I mustn't have dusted
you mustn't have dusted
she mustn't have dusted
we mustn't have dusted
you mustn't have dusted
they mustn't have dusted	I mustn't have been dusting
you mustn't have been dusting
she mustn't have been dusting
we mustn't have been dusting
you mustn't have been dusting
they mustn't have been dusting	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I dust?
must you dust?
must she dust?
must we dust?
must you dust?
must they dust? 	must I be dusting?
must you be dusting?
must she be dusting?
must we be dusting?
must you be dusting?
must they be dusting? 	must I have dusted?
must you have dusted?
must she have dusted?
must we have dusted?
must you have dusted?
must they have dusted? 	must I have been dusting?
must you have been dusting?
must she have been dusting?
must we have been dusting?
must you have been dusting?
must they have been dusting? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
mustn't I dust?
mustn't you dust?
mustn't she dust?
mustn't we dust?
mustn't you dust?
mustn't they dust? 	mustn't I be dusting?
mustn't you be dusting?
mustn't she be dusting?
mustn't we be dusting?
mustn't you be dusting?
mustn't they be dusting? 	mustn't I have dusted?
mustn't you have dusted?
mustn't she have dusted?
mustn't we have dusted?
mustn't you have dusted?
mustn't they have dusted? 	mustn't I have been dusting?
mustn't you have been dusting?
mustn't she have been dusting?
mustn't we have been dusting?
mustn't you have been dusting?
mustn't they have been dusting?