must tube
Verbo regular: tube - tubed- tubed

Afirmación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I must tube
you must tube
he must tube
we must tube
you must tube
they must tube 	I must be tubing
you must be tubing
he must be tubing
we must be tubing
you must be tubing
they must be tubing	I must have tubed
you must have tubed
he must have tubed
we must have tubed
you must have tubed
they must have tubed	I must have been tubing
you must have been tubing
he must have been tubing
we must have been tubing
you must have been tubing
they must have been tubing	

Negación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I must not tube
you must not tube
he must not tube
we must not tube
you must not tube
they must not tube 	I must not be tubing
you must not be tubing
he must not be tubing
we must not be tubing
you must not be tubing
they must not be tubing	I must not have tubed
you must not have tubed
he must not have tubed
we must not have tubed
you must not have tubed
they must not have tubed	I must not have been tubing
you must not have been tubing
he must not have been tubing
we must not have been tubing
you must not have been tubing
they must not have been tubing	

Forma interrogativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
must I tube?
must you tube?
must he tube?
must we tube?
must you tube?
must they tube? 	must I be tubing?
must you be tubing?
must he be tubing?
must we be tubing?
must you be tubing?
must they be tubing? 	must I have tubed?
must you have tubed?
must he have tubed?
must we have tubed?
must you have tubed?
must they have tubed? 	must I have been tubing?
must you have been tubing?
must he have been tubing?
must we have been tubing?
must you have been tubing?
must they have been tubing? 	

Forma interro-negativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
must I not tube?
must you not tube?
must he not tube?
must we not tube?
must you not tube?
must they not tube? 	must I not be tubing?
must you not be tubing?
must he not be tubing?
must we not be tubing?
must you not be tubing?
must they not be tubing? 	must I not have tubed?
must you not have tubed?
must he not have tubed?
must we not have tubed?
must you not have tubed?
must they not have tubed? 	must I not have been tubing?
must you not have been tubing?
must he not have been tubing?
must we not have been tubing?
must you not have been tubing?
must they not have been tubing?