must grade
Verbo regular: grade - graded- graded

Afirmación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I must grade
you must grade
he must grade
we must grade
you must grade
they must grade 	I must be grading
you must be grading
he must be grading
we must be grading
you must be grading
they must be grading	I must have graded
you must have graded
he must have graded
we must have graded
you must have graded
they must have graded	I must have been grading
you must have been grading
he must have been grading
we must have been grading
you must have been grading
they must have been grading	

Negación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I mustn't grade
you mustn't grade
he mustn't grade
we mustn't grade
you mustn't grade
they mustn't grade 	I mustn't be grading
you mustn't be grading
he mustn't be grading
we mustn't be grading
you mustn't be grading
they mustn't be grading	I mustn't have graded
you mustn't have graded
he mustn't have graded
we mustn't have graded
you mustn't have graded
they mustn't have graded	I mustn't have been grading
you mustn't have been grading
he mustn't have been grading
we mustn't have been grading
you mustn't have been grading
they mustn't have been grading	

Forma interrogativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
must I grade?
must you grade?
must he grade?
must we grade?
must you grade?
must they grade? 	must I be grading?
must you be grading?
must he be grading?
must we be grading?
must you be grading?
must they be grading? 	must I have graded?
must you have graded?
must he have graded?
must we have graded?
must you have graded?
must they have graded? 	must I have been grading?
must you have been grading?
must he have been grading?
must we have been grading?
must you have been grading?
must they have been grading? 	

Forma interro-negativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
mustn't I grade?
mustn't you grade?
mustn't he grade?
mustn't we grade?
mustn't you grade?
mustn't they grade? 	mustn't I be grading?
mustn't you be grading?
mustn't he be grading?
mustn't we be grading?
mustn't you be grading?
mustn't they be grading? 	mustn't I have graded?
mustn't you have graded?
mustn't he have graded?
mustn't we have graded?
mustn't you have graded?
mustn't they have graded? 	mustn't I have been grading?
mustn't you have been grading?
mustn't he have been grading?
mustn't we have been grading?
mustn't you have been grading?
mustn't they have been grading?