must costume
Regular verb: costume - costumed- costumed

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must costume
you must costume
he must costume
we must costume
you must costume
they must costume 	I must be costuming
you must be costuming
he must be costuming
we must be costuming
you must be costuming
they must be costuming	I must have costumed
you must have costumed
he must have costumed
we must have costumed
you must have costumed
they must have costumed	I must have been costuming
you must have been costuming
he must have been costuming
we must have been costuming
you must have been costuming
they must have been costuming	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I mustn't costume
you mustn't costume
he mustn't costume
we mustn't costume
you mustn't costume
they mustn't costume 	I mustn't be costuming
you mustn't be costuming
he mustn't be costuming
we mustn't be costuming
you mustn't be costuming
they mustn't be costuming	I mustn't have costumed
you mustn't have costumed
he mustn't have costumed
we mustn't have costumed
you mustn't have costumed
they mustn't have costumed	I mustn't have been costuming
you mustn't have been costuming
he mustn't have been costuming
we mustn't have been costuming
you mustn't have been costuming
they mustn't have been costuming	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I costume?
must you costume?
must he costume?
must we costume?
must you costume?
must they costume? 	must I be costuming?
must you be costuming?
must he be costuming?
must we be costuming?
must you be costuming?
must they be costuming? 	must I have costumed?
must you have costumed?
must he have costumed?
must we have costumed?
must you have costumed?
must they have costumed? 	must I have been costuming?
must you have been costuming?
must he have been costuming?
must we have been costuming?
must you have been costuming?
must they have been costuming? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
mustn't I costume?
mustn't you costume?
mustn't he costume?
mustn't we costume?
mustn't you costume?
mustn't they costume? 	mustn't I be costuming?
mustn't you be costuming?
mustn't he be costuming?
mustn't we be costuming?
mustn't you be costuming?
mustn't they be costuming? 	mustn't I have costumed?
mustn't you have costumed?
mustn't he have costumed?
mustn't we have costumed?
mustn't you have costumed?
mustn't they have costumed? 	mustn't I have been costuming?
mustn't you have been costuming?
mustn't he have been costuming?
mustn't we have been costuming?
mustn't you have been costuming?
mustn't they have been costuming?