must prealter
Verbo regular: prealter - prealtered- prealtered

Afirmación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I must prealter
you must prealter
he must prealter
we must prealter
you must prealter
they must prealter 	I must be prealtering
you must be prealtering
he must be prealtering
we must be prealtering
you must be prealtering
they must be prealtering	I must have prealtered
you must have prealtered
he must have prealtered
we must have prealtered
you must have prealtered
they must have prealtered	I must have been prealtering
you must have been prealtering
he must have been prealtering
we must have been prealtering
you must have been prealtering
they must have been prealtering	

Negación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I mustn't prealter
you mustn't prealter
he mustn't prealter
we mustn't prealter
you mustn't prealter
they mustn't prealter 	I mustn't be prealtering
you mustn't be prealtering
he mustn't be prealtering
we mustn't be prealtering
you mustn't be prealtering
they mustn't be prealtering	I mustn't have prealtered
you mustn't have prealtered
he mustn't have prealtered
we mustn't have prealtered
you mustn't have prealtered
they mustn't have prealtered	I mustn't have been prealtering
you mustn't have been prealtering
he mustn't have been prealtering
we mustn't have been prealtering
you mustn't have been prealtering
they mustn't have been prealtering	

Forma interrogativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
must I prealter?
must you prealter?
must he prealter?
must we prealter?
must you prealter?
must they prealter? 	must I be prealtering?
must you be prealtering?
must he be prealtering?
must we be prealtering?
must you be prealtering?
must they be prealtering? 	must I have prealtered?
must you have prealtered?
must he have prealtered?
must we have prealtered?
must you have prealtered?
must they have prealtered? 	must I have been prealtering?
must you have been prealtering?
must he have been prealtering?
must we have been prealtering?
must you have been prealtering?
must they have been prealtering? 	

Forma interro-negativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
mustn't I prealter?
mustn't you prealter?
mustn't he prealter?
mustn't we prealter?
mustn't you prealter?
mustn't they prealter? 	mustn't I be prealtering?
mustn't you be prealtering?
mustn't he be prealtering?
mustn't we be prealtering?
mustn't you be prealtering?
mustn't they be prealtering? 	mustn't I have prealtered?
mustn't you have prealtered?
mustn't he have prealtered?
mustn't we have prealtered?
mustn't you have prealtered?
mustn't they have prealtered? 	mustn't I have been prealtering?
mustn't you have been prealtering?
mustn't he have been prealtering?
mustn't we have been prealtering?
mustn't you have been prealtering?
mustn't they have been prealtering?