must refrain
Regular verb: refrain - refrained- refrained

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must refrain
you must refrain
she must refrain
we must refrain
you must refrain
they must refrain 	I must be refraining
you must be refraining
she must be refraining
we must be refraining
you must be refraining
they must be refraining	I must have refrained
you must have refrained
she must have refrained
we must have refrained
you must have refrained
they must have refrained	I must have been refraining
you must have been refraining
she must have been refraining
we must have been refraining
you must have been refraining
they must have been refraining	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I mustn't refrain
you mustn't refrain
she mustn't refrain
we mustn't refrain
you mustn't refrain
they mustn't refrain 	I mustn't be refraining
you mustn't be refraining
she mustn't be refraining
we mustn't be refraining
you mustn't be refraining
they mustn't be refraining	I mustn't have refrained
you mustn't have refrained
she mustn't have refrained
we mustn't have refrained
you mustn't have refrained
they mustn't have refrained	I mustn't have been refraining
you mustn't have been refraining
she mustn't have been refraining
we mustn't have been refraining
you mustn't have been refraining
they mustn't have been refraining	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I refrain?
must you refrain?
must she refrain?
must we refrain?
must you refrain?
must they refrain? 	must I be refraining?
must you be refraining?
must she be refraining?
must we be refraining?
must you be refraining?
must they be refraining? 	must I have refrained?
must you have refrained?
must she have refrained?
must we have refrained?
must you have refrained?
must they have refrained? 	must I have been refraining?
must you have been refraining?
must she have been refraining?
must we have been refraining?
must you have been refraining?
must they have been refraining? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
mustn't I refrain?
mustn't you refrain?
mustn't she refrain?
mustn't we refrain?
mustn't you refrain?
mustn't they refrain? 	mustn't I be refraining?
mustn't you be refraining?
mustn't she be refraining?
mustn't we be refraining?
mustn't you be refraining?
mustn't they be refraining? 	mustn't I have refrained?
mustn't you have refrained?
mustn't she have refrained?
mustn't we have refrained?
mustn't you have refrained?
mustn't they have refrained? 	mustn't I have been refraining?
mustn't you have been refraining?
mustn't she have been refraining?
mustn't we have been refraining?
mustn't you have been refraining?
mustn't they have been refraining?