must umber
Verbo regular: umber - umbered- umbered

Afirmación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I must umber
you must umber
he must umber
we must umber
you must umber
they must umber 	I must be umbering
you must be umbering
he must be umbering
we must be umbering
you must be umbering
they must be umbering	I must have umbered
you must have umbered
he must have umbered
we must have umbered
you must have umbered
they must have umbered	I must have been umbering
you must have been umbering
he must have been umbering
we must have been umbering
you must have been umbering
they must have been umbering	

Negación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I must not umber
you must not umber
he must not umber
we must not umber
you must not umber
they must not umber 	I must not be umbering
you must not be umbering
he must not be umbering
we must not be umbering
you must not be umbering
they must not be umbering	I must not have umbered
you must not have umbered
he must not have umbered
we must not have umbered
you must not have umbered
they must not have umbered	I must not have been umbering
you must not have been umbering
he must not have been umbering
we must not have been umbering
you must not have been umbering
they must not have been umbering	

Forma interrogativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
must I umber?
must you umber?
must he umber?
must we umber?
must you umber?
must they umber? 	must I be umbering?
must you be umbering?
must he be umbering?
must we be umbering?
must you be umbering?
must they be umbering? 	must I have umbered?
must you have umbered?
must he have umbered?
must we have umbered?
must you have umbered?
must they have umbered? 	must I have been umbering?
must you have been umbering?
must he have been umbering?
must we have been umbering?
must you have been umbering?
must they have been umbering? 	

Forma interro-negativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
must I not umber?
must you not umber?
must he not umber?
must we not umber?
must you not umber?
must they not umber? 	must I not be umbering?
must you not be umbering?
must he not be umbering?
must we not be umbering?
must you not be umbering?
must they not be umbering? 	must I not have umbered?
must you not have umbered?
must he not have umbered?
must we not have umbered?
must you not have umbered?
must they not have umbered? 	must I not have been umbering?
must you not have been umbering?
must he not have been umbering?
must we not have been umbering?
must you not have been umbering?
must they not have been umbering?