must whiten
Verbo regular: whiten - whitened- whitened

Afirmación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I must whiten
you must whiten
he must whiten
we must whiten
you must whiten
they must whiten 	I must be whitening
you must be whitening
he must be whitening
we must be whitening
you must be whitening
they must be whitening	I must have whitened
you must have whitened
he must have whitened
we must have whitened
you must have whitened
they must have whitened	I must have been whitening
you must have been whitening
he must have been whitening
we must have been whitening
you must have been whitening
they must have been whitening	

Negación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I must not whiten
you must not whiten
he must not whiten
we must not whiten
you must not whiten
they must not whiten 	I must not be whitening
you must not be whitening
he must not be whitening
we must not be whitening
you must not be whitening
they must not be whitening	I must not have whitened
you must not have whitened
he must not have whitened
we must not have whitened
you must not have whitened
they must not have whitened	I must not have been whitening
you must not have been whitening
he must not have been whitening
we must not have been whitening
you must not have been whitening
they must not have been whitening	

Forma interrogativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
must I whiten?
must you whiten?
must he whiten?
must we whiten?
must you whiten?
must they whiten? 	must I be whitening?
must you be whitening?
must he be whitening?
must we be whitening?
must you be whitening?
must they be whitening? 	must I have whitened?
must you have whitened?
must he have whitened?
must we have whitened?
must you have whitened?
must they have whitened? 	must I have been whitening?
must you have been whitening?
must he have been whitening?
must we have been whitening?
must you have been whitening?
must they have been whitening? 	

Forma interro-negativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
must I not whiten?
must you not whiten?
must he not whiten?
must we not whiten?
must you not whiten?
must they not whiten? 	must I not be whitening?
must you not be whitening?
must he not be whitening?
must we not be whitening?
must you not be whitening?
must they not be whitening? 	must I not have whitened?
must you not have whitened?
must he not have whitened?
must we not have whitened?
must you not have whitened?
must they not have whitened? 	must I not have been whitening?
must you not have been whitening?
must he not have been whitening?
must we not have been whitening?
must you not have been whitening?
must they not have been whitening?