must blacken
Verbo regular: blacken - blackened- blackened

Afirmação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I must blacken
you must blacken
he must blacken
we must blacken
you must blacken
they must blacken 	I must be blackening
you must be blackening
he must be blackening
we must be blackening
you must be blackening
they must be blackening	I must have blackened
you must have blackened
he must have blackened
we must have blackened
you must have blackened
they must have blackened	I must have been blackening
you must have been blackening
he must have been blackening
we must have been blackening
you must have been blackening
they must have been blackening	

Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
I mustn't blacken
you mustn't blacken
he mustn't blacken
we mustn't blacken
you mustn't blacken
they mustn't blacken 	I mustn't be blackening
you mustn't be blackening
he mustn't be blackening
we mustn't be blackening
you mustn't be blackening
they mustn't be blackening	I mustn't have blackened
you mustn't have blackened
he mustn't have blackened
we mustn't have blackened
you mustn't have blackened
they mustn't have blackened	I mustn't have been blackening
you mustn't have been blackening
he mustn't have been blackening
we mustn't have been blackening
you mustn't have been blackening
they mustn't have been blackening	

Forma interrogativa 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
must I blacken?
must you blacken?
must he blacken?
must we blacken?
must you blacken?
must they blacken? 	must I be blackening?
must you be blackening?
must he be blackening?
must we be blackening?
must you be blackening?
must they be blackening? 	must I have blackened?
must you have blackened?
must he have blackened?
must we have blackened?
must you have blackened?
must they have blackened? 	must I have been blackening?
must you have been blackening?
must he have been blackening?
must we have been blackening?
must you have been blackening?
must they have been blackening? 	

Forma interro-Negação 	
Forma simple 	Forma com V-ing 	Perfeito 	Perfeito com V-ing 	
mustn't I blacken?
mustn't you blacken?
mustn't he blacken?
mustn't we blacken?
mustn't you blacken?
mustn't they blacken? 	mustn't I be blackening?
mustn't you be blackening?
mustn't he be blackening?
mustn't we be blackening?
mustn't you be blackening?
mustn't they be blackening? 	mustn't I have blackened?
mustn't you have blackened?
mustn't he have blackened?
mustn't we have blackened?
mustn't you have blackened?
mustn't they have blackened? 	mustn't I have been blackening?
mustn't you have been blackening?
mustn't he have been blackening?
mustn't we have been blackening?
mustn't you have been blackening?
mustn't they have been blackening?