must fast-forward
Regular verb: fast-forward - fast-forwarded- fast-forwarded

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must fast-forward
you must fast-forward
he must fast-forward
we must fast-forward
you must fast-forward
they must fast-forward 	I must be fast-forwarding
you must be fast-forwarding
he must be fast-forwarding
we must be fast-forwarding
you must be fast-forwarding
they must be fast-forwarding	I must have fast-forwarded
you must have fast-forwarded
he must have fast-forwarded
we must have fast-forwarded
you must have fast-forwarded
they must have fast-forwarded	I must have been fast-forwarding
you must have been fast-forwarding
he must have been fast-forwarding
we must have been fast-forwarding
you must have been fast-forwarding
they must have been fast-forwarding	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I mustn't fast-forward
you mustn't fast-forward
he mustn't fast-forward
we mustn't fast-forward
you mustn't fast-forward
they mustn't fast-forward 	I mustn't be fast-forwarding
you mustn't be fast-forwarding
he mustn't be fast-forwarding
we mustn't be fast-forwarding
you mustn't be fast-forwarding
they mustn't be fast-forwarding	I mustn't have fast-forwarded
you mustn't have fast-forwarded
he mustn't have fast-forwarded
we mustn't have fast-forwarded
you mustn't have fast-forwarded
they mustn't have fast-forwarded	I mustn't have been fast-forwarding
you mustn't have been fast-forwarding
he mustn't have been fast-forwarding
we mustn't have been fast-forwarding
you mustn't have been fast-forwarding
they mustn't have been fast-forwarding	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I fast-forward?
must you fast-forward?
must he fast-forward?
must we fast-forward?
must you fast-forward?
must they fast-forward? 	must I be fast-forwarding?
must you be fast-forwarding?
must he be fast-forwarding?
must we be fast-forwarding?
must you be fast-forwarding?
must they be fast-forwarding? 	must I have fast-forwarded?
must you have fast-forwarded?
must he have fast-forwarded?
must we have fast-forwarded?
must you have fast-forwarded?
must they have fast-forwarded? 	must I have been fast-forwarding?
must you have been fast-forwarding?
must he have been fast-forwarding?
must we have been fast-forwarding?
must you have been fast-forwarding?
must they have been fast-forwarding? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
mustn't I fast-forward?
mustn't you fast-forward?
mustn't he fast-forward?
mustn't we fast-forward?
mustn't you fast-forward?
mustn't they fast-forward? 	mustn't I be fast-forwarding?
mustn't you be fast-forwarding?
mustn't he be fast-forwarding?
mustn't we be fast-forwarding?
mustn't you be fast-forwarding?
mustn't they be fast-forwarding? 	mustn't I have fast-forwarded?
mustn't you have fast-forwarded?
mustn't he have fast-forwarded?
mustn't we have fast-forwarded?
mustn't you have fast-forwarded?
mustn't they have fast-forwarded? 	mustn't I have been fast-forwarding?
mustn't you have been fast-forwarding?
mustn't he have been fast-forwarding?
mustn't we have been fast-forwarding?
mustn't you have been fast-forwarding?
mustn't they have been fast-forwarding?