must refract
Verbo regular: refract - refracted- refracted

Afirmação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I must refract
you must refract
he must refract
we must refract
you must refract
they must refract 	I must be refracting
you must be refracting
he must be refracting
we must be refracting
you must be refracting
they must be refracting	I must have refracted
you must have refracted
he must have refracted
we must have refracted
you must have refracted
they must have refracted	I must have been refracting
you must have been refracting
he must have been refracting
we must have been refracting
you must have been refracting
they must have been refracting	

Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I mustn't refract
you mustn't refract
he mustn't refract
we mustn't refract
you mustn't refract
they mustn't refract 	I mustn't be refracting
you mustn't be refracting
he mustn't be refracting
we mustn't be refracting
you mustn't be refracting
they mustn't be refracting	I mustn't have refracted
you mustn't have refracted
he mustn't have refracted
we mustn't have refracted
you mustn't have refracted
they mustn't have refracted	I mustn't have been refracting
you mustn't have been refracting
he mustn't have been refracting
we mustn't have been refracting
you mustn't have been refracting
they mustn't have been refracting	

Forma interrogativa 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
must I refract?
must you refract?
must he refract?
must we refract?
must you refract?
must they refract? 	must I be refracting?
must you be refracting?
must he be refracting?
must we be refracting?
must you be refracting?
must they be refracting? 	must I have refracted?
must you have refracted?
must he have refracted?
must we have refracted?
must you have refracted?
must they have refracted? 	must I have been refracting?
must you have been refracting?
must he have been refracting?
must we have been refracting?
must you have been refracting?
must they have been refracting? 	

Forma interro-Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
mustn't I refract?
mustn't you refract?
mustn't he refract?
mustn't we refract?
mustn't you refract?
mustn't they refract? 	mustn't I be refracting?
mustn't you be refracting?
mustn't he be refracting?
mustn't we be refracting?
mustn't you be refracting?
mustn't they be refracting? 	mustn't I have refracted?
mustn't you have refracted?
mustn't he have refracted?
mustn't we have refracted?
mustn't you have refracted?
mustn't they have refracted? 	mustn't I have been refracting?
mustn't you have been refracting?
mustn't he have been refracting?
mustn't we have been refracting?
mustn't you have been refracting?
mustn't they have been refracting?