must fuss
Regular verb: fuss - fussed- fussed

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must fuss
you must fuss
he must fuss
we must fuss
you must fuss
they must fuss 	I must be fussing
you must be fussing
he must be fussing
we must be fussing
you must be fussing
they must be fussing	I must have fussed
you must have fussed
he must have fussed
we must have fussed
you must have fussed
they must have fussed	I must have been fussing
you must have been fussing
he must have been fussing
we must have been fussing
you must have been fussing
they must have been fussing	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I mustn't fuss
you mustn't fuss
he mustn't fuss
we mustn't fuss
you mustn't fuss
they mustn't fuss 	I mustn't be fussing
you mustn't be fussing
he mustn't be fussing
we mustn't be fussing
you mustn't be fussing
they mustn't be fussing	I mustn't have fussed
you mustn't have fussed
he mustn't have fussed
we mustn't have fussed
you mustn't have fussed
they mustn't have fussed	I mustn't have been fussing
you mustn't have been fussing
he mustn't have been fussing
we mustn't have been fussing
you mustn't have been fussing
they mustn't have been fussing	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I fuss?
must you fuss?
must he fuss?
must we fuss?
must you fuss?
must they fuss? 	must I be fussing?
must you be fussing?
must he be fussing?
must we be fussing?
must you be fussing?
must they be fussing? 	must I have fussed?
must you have fussed?
must he have fussed?
must we have fussed?
must you have fussed?
must they have fussed? 	must I have been fussing?
must you have been fussing?
must he have been fussing?
must we have been fussing?
must you have been fussing?
must they have been fussing? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
mustn't I fuss?
mustn't you fuss?
mustn't he fuss?
mustn't we fuss?
mustn't you fuss?
mustn't they fuss? 	mustn't I be fussing?
mustn't you be fussing?
mustn't he be fussing?
mustn't we be fussing?
mustn't you be fussing?
mustn't they be fussing? 	mustn't I have fussed?
mustn't you have fussed?
mustn't he have fussed?
mustn't we have fussed?
mustn't you have fussed?
mustn't they have fussed? 	mustn't I have been fussing?
mustn't you have been fussing?
mustn't he have been fussing?
mustn't we have been fussing?
mustn't you have been fussing?
mustn't they have been fussing?