must saber
Verbo regular: saber - sabered- sabered

Afirmación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I must saber
you must saber
he must saber
we must saber
you must saber
they must saber 	I must be sabering
you must be sabering
he must be sabering
we must be sabering
you must be sabering
they must be sabering	I must have sabered
you must have sabered
he must have sabered
we must have sabered
you must have sabered
they must have sabered	I must have been sabering
you must have been sabering
he must have been sabering
we must have been sabering
you must have been sabering
they must have been sabering	

Negación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I must not saber
you must not saber
he must not saber
we must not saber
you must not saber
they must not saber 	I must not be sabering
you must not be sabering
he must not be sabering
we must not be sabering
you must not be sabering
they must not be sabering	I must not have sabered
you must not have sabered
he must not have sabered
we must not have sabered
you must not have sabered
they must not have sabered	I must not have been sabering
you must not have been sabering
he must not have been sabering
we must not have been sabering
you must not have been sabering
they must not have been sabering	

Forma interrogativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
must I saber?
must you saber?
must he saber?
must we saber?
must you saber?
must they saber? 	must I be sabering?
must you be sabering?
must he be sabering?
must we be sabering?
must you be sabering?
must they be sabering? 	must I have sabered?
must you have sabered?
must he have sabered?
must we have sabered?
must you have sabered?
must they have sabered? 	must I have been sabering?
must you have been sabering?
must he have been sabering?
must we have been sabering?
must you have been sabering?
must they have been sabering? 	

Forma interro-negativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
must I not saber?
must you not saber?
must he not saber?
must we not saber?
must you not saber?
must they not saber? 	must I not be sabering?
must you not be sabering?
must he not be sabering?
must we not be sabering?
must you not be sabering?
must they not be sabering? 	must I not have sabered?
must you not have sabered?
must he not have sabered?
must we not have sabered?
must you not have sabered?
must they not have sabered? 	must I not have been sabering?
must you not have been sabering?
must he not have been sabering?
must we not have been sabering?
must you not have been sabering?
must they not have been sabering?