must stifle
Verbo regular: stifle - stifled- stifled

Afirmación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I must stifle
you must stifle
he must stifle
we must stifle
you must stifle
they must stifle 	I must be stifling
you must be stifling
he must be stifling
we must be stifling
you must be stifling
they must be stifling	I must have stifled
you must have stifled
he must have stifled
we must have stifled
you must have stifled
they must have stifled	I must have been stifling
you must have been stifling
he must have been stifling
we must have been stifling
you must have been stifling
they must have been stifling	

Negación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I must not stifle
you must not stifle
he must not stifle
we must not stifle
you must not stifle
they must not stifle 	I must not be stifling
you must not be stifling
he must not be stifling
we must not be stifling
you must not be stifling
they must not be stifling	I must not have stifled
you must not have stifled
he must not have stifled
we must not have stifled
you must not have stifled
they must not have stifled	I must not have been stifling
you must not have been stifling
he must not have been stifling
we must not have been stifling
you must not have been stifling
they must not have been stifling	

Forma interrogativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
must I stifle?
must you stifle?
must he stifle?
must we stifle?
must you stifle?
must they stifle? 	must I be stifling?
must you be stifling?
must he be stifling?
must we be stifling?
must you be stifling?
must they be stifling? 	must I have stifled?
must you have stifled?
must he have stifled?
must we have stifled?
must you have stifled?
must they have stifled? 	must I have been stifling?
must you have been stifling?
must he have been stifling?
must we have been stifling?
must you have been stifling?
must they have been stifling? 	

Forma interro-negativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
must I not stifle?
must you not stifle?
must he not stifle?
must we not stifle?
must you not stifle?
must they not stifle? 	must I not be stifling?
must you not be stifling?
must he not be stifling?
must we not be stifling?
must you not be stifling?
must they not be stifling? 	must I not have stifled?
must you not have stifled?
must he not have stifled?
must we not have stifled?
must you not have stifled?
must they not have stifled? 	must I not have been stifling?
must you not have been stifling?
must he not have been stifling?
must we not have been stifling?
must you not have been stifling?
must they not have been stifling?