must amuse
Regular verb: amuse - amused- amused

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must amuse
you must amuse
he must amuse
we must amuse
you must amuse
they must amuse 	I must be amusing
you must be amusing
he must be amusing
we must be amusing
you must be amusing
they must be amusing	I must have amused
you must have amused
he must have amused
we must have amused
you must have amused
they must have amused	I must have been amusing
you must have been amusing
he must have been amusing
we must have been amusing
you must have been amusing
they must have been amusing	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I mustn't amuse
you mustn't amuse
he mustn't amuse
we mustn't amuse
you mustn't amuse
they mustn't amuse 	I mustn't be amusing
you mustn't be amusing
he mustn't be amusing
we mustn't be amusing
you mustn't be amusing
they mustn't be amusing	I mustn't have amused
you mustn't have amused
he mustn't have amused
we mustn't have amused
you mustn't have amused
they mustn't have amused	I mustn't have been amusing
you mustn't have been amusing
he mustn't have been amusing
we mustn't have been amusing
you mustn't have been amusing
they mustn't have been amusing	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I amuse?
must you amuse?
must he amuse?
must we amuse?
must you amuse?
must they amuse? 	must I be amusing?
must you be amusing?
must he be amusing?
must we be amusing?
must you be amusing?
must they be amusing? 	must I have amused?
must you have amused?
must he have amused?
must we have amused?
must you have amused?
must they have amused? 	must I have been amusing?
must you have been amusing?
must he have been amusing?
must we have been amusing?
must you have been amusing?
must they have been amusing? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
mustn't I amuse?
mustn't you amuse?
mustn't he amuse?
mustn't we amuse?
mustn't you amuse?
mustn't they amuse? 	mustn't I be amusing?
mustn't you be amusing?
mustn't he be amusing?
mustn't we be amusing?
mustn't you be amusing?
mustn't they be amusing? 	mustn't I have amused?
mustn't you have amused?
mustn't he have amused?
mustn't we have amused?
mustn't you have amused?
mustn't they have amused? 	mustn't I have been amusing?
mustn't you have been amusing?
mustn't he have been amusing?
mustn't we have been amusing?
mustn't you have been amusing?
mustn't they have been amusing?