must grab
Verbo regular: grab - grabbed- grabbed

Afirmación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I must grab
you must grab
he must grab
we must grab
you must grab
they must grab 	I must be grabbing
you must be grabbing
he must be grabbing
we must be grabbing
you must be grabbing
they must be grabbing	I must have grabbed
you must have grabbed
he must have grabbed
we must have grabbed
you must have grabbed
they must have grabbed	I must have been grabbing
you must have been grabbing
he must have been grabbing
we must have been grabbing
you must have been grabbing
they must have been grabbing	

Negación 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
I must not grab
you must not grab
he must not grab
we must not grab
you must not grab
they must not grab 	I must not be grabbing
you must not be grabbing
he must not be grabbing
we must not be grabbing
you must not be grabbing
they must not be grabbing	I must not have grabbed
you must not have grabbed
he must not have grabbed
we must not have grabbed
you must not have grabbed
they must not have grabbed	I must not have been grabbing
you must not have been grabbing
he must not have been grabbing
we must not have been grabbing
you must not have been grabbing
they must not have been grabbing	

Forma interrogativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
must I grab?
must you grab?
must he grab?
must we grab?
must you grab?
must they grab? 	must I be grabbing?
must you be grabbing?
must he be grabbing?
must we be grabbing?
must you be grabbing?
must they be grabbing? 	must I have grabbed?
must you have grabbed?
must he have grabbed?
must we have grabbed?
must you have grabbed?
must they have grabbed? 	must I have been grabbing?
must you have been grabbing?
must he have been grabbing?
must we have been grabbing?
must you have been grabbing?
must they have been grabbing? 	

Forma interro-negativa 	
Forma simple 	Forma con V-ing 	Perfecto 	Perfecto con V-ing 	
must I not grab?
must you not grab?
must he not grab?
must we not grab?
must you not grab?
must they not grab? 	must I not be grabbing?
must you not be grabbing?
must he not be grabbing?
must we not be grabbing?
must you not be grabbing?
must they not be grabbing? 	must I not have grabbed?
must you not have grabbed?
must he not have grabbed?
must we not have grabbed?
must you not have grabbed?
must they not have grabbed? 	must I not have been grabbing?
must you not have been grabbing?
must he not have been grabbing?
must we not have been grabbing?
must you not have been grabbing?
must they not have been grabbing?