must grin
Verbo regular: grin - grinned- grinned

Afirmación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I must grin
you must grin
he must grin
we must grin
you must grin
they must grin 	I must be grinning
you must be grinning
he must be grinning
we must be grinning
you must be grinning
they must be grinning	I must have grinned
you must have grinned
he must have grinned
we must have grinned
you must have grinned
they must have grinned	I must have been grinning
you must have been grinning
he must have been grinning
we must have been grinning
you must have been grinning
they must have been grinning	

Negación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I must not grin
you must not grin
he must not grin
we must not grin
you must not grin
they must not grin 	I must not be grinning
you must not be grinning
he must not be grinning
we must not be grinning
you must not be grinning
they must not be grinning	I must not have grinned
you must not have grinned
he must not have grinned
we must not have grinned
you must not have grinned
they must not have grinned	I must not have been grinning
you must not have been grinning
he must not have been grinning
we must not have been grinning
you must not have been grinning
they must not have been grinning	

Forma interrogativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
must I grin?
must you grin?
must he grin?
must we grin?
must you grin?
must they grin? 	must I be grinning?
must you be grinning?
must he be grinning?
must we be grinning?
must you be grinning?
must they be grinning? 	must I have grinned?
must you have grinned?
must he have grinned?
must we have grinned?
must you have grinned?
must they have grinned? 	must I have been grinning?
must you have been grinning?
must he have been grinning?
must we have been grinning?
must you have been grinning?
must they have been grinning? 	

Forma interro-negativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
must I not grin?
must you not grin?
must he not grin?
must we not grin?
must you not grin?
must they not grin? 	must I not be grinning?
must you not be grinning?
must he not be grinning?
must we not be grinning?
must you not be grinning?
must they not be grinning? 	must I not have grinned?
must you not have grinned?
must he not have grinned?
must we not have grinned?
must you not have grinned?
must they not have grinned? 	must I not have been grinning?
must you not have been grinning?
must he not have been grinning?
must we not have been grinning?
must you not have been grinning?
must they not have been grinning?