must frank
Verbo regular: frank - franked- franked

Afirmación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I must frank
you must frank
he must frank
we must frank
you must frank
they must frank 	I must be franking
you must be franking
he must be franking
we must be franking
you must be franking
they must be franking	I must have franked
you must have franked
he must have franked
we must have franked
you must have franked
they must have franked	I must have been franking
you must have been franking
he must have been franking
we must have been franking
you must have been franking
they must have been franking	

Negación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I must not frank
you must not frank
he must not frank
we must not frank
you must not frank
they must not frank 	I must not be franking
you must not be franking
he must not be franking
we must not be franking
you must not be franking
they must not be franking	I must not have franked
you must not have franked
he must not have franked
we must not have franked
you must not have franked
they must not have franked	I must not have been franking
you must not have been franking
he must not have been franking
we must not have been franking
you must not have been franking
they must not have been franking	

Forma interrogativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
must I frank?
must you frank?
must he frank?
must we frank?
must you frank?
must they frank? 	must I be franking?
must you be franking?
must he be franking?
must we be franking?
must you be franking?
must they be franking? 	must I have franked?
must you have franked?
must he have franked?
must we have franked?
must you have franked?
must they have franked? 	must I have been franking?
must you have been franking?
must he have been franking?
must we have been franking?
must you have been franking?
must they have been franking? 	

Forma interro-negativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
must I not frank?
must you not frank?
must he not frank?
must we not frank?
must you not frank?
must they not frank? 	must I not be franking?
must you not be franking?
must he not be franking?
must we not be franking?
must you not be franking?
must they not be franking? 	must I not have franked?
must you not have franked?
must he not have franked?
must we not have franked?
must you not have franked?
must they not have franked? 	must I not have been franking?
must you not have been franking?
must he not have been franking?
must we not have been franking?
must you not have been franking?
must they not have been franking?