English verb conjugation
MUST REFRAIN

Regular verb: refrain - refrained - refrained

Affirmation

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