must staple
Regular verb: staple - stapled- stapled

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I must staple
you must staple
he must staple
we must staple
you must staple
they must staple 	I must be stapling
you must be stapling
he must be stapling
we must be stapling
you must be stapling
they must be stapling	I must have stapled
you must have stapled
he must have stapled
we must have stapled
you must have stapled
they must have stapled	I must have been stapling
you must have been stapling
he must have been stapling
we must have been stapling
you must have been stapling
they must have been stapling	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I mustn't staple
you mustn't staple
he mustn't staple
we mustn't staple
you mustn't staple
they mustn't staple 	I mustn't be stapling
you mustn't be stapling
he mustn't be stapling
we mustn't be stapling
you mustn't be stapling
they mustn't be stapling	I mustn't have stapled
you mustn't have stapled
he mustn't have stapled
we mustn't have stapled
you mustn't have stapled
they mustn't have stapled	I mustn't have been stapling
you mustn't have been stapling
he mustn't have been stapling
we mustn't have been stapling
you mustn't have been stapling
they mustn't have been stapling	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
must I staple?
must you staple?
must he staple?
must we staple?
must you staple?
must they staple? 	must I be stapling?
must you be stapling?
must he be stapling?
must we be stapling?
must you be stapling?
must they be stapling? 	must I have stapled?
must you have stapled?
must he have stapled?
must we have stapled?
must you have stapled?
must they have stapled? 	must I have been stapling?
must you have been stapling?
must he have been stapling?
must we have been stapling?
must you have been stapling?
must they have been stapling? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
mustn't I staple?
mustn't you staple?
mustn't he staple?
mustn't we staple?
mustn't you staple?
mustn't they staple? 	mustn't I be stapling?
mustn't you be stapling?
mustn't he be stapling?
mustn't we be stapling?
mustn't you be stapling?
mustn't they be stapling? 	mustn't I have stapled?
mustn't you have stapled?
mustn't he have stapled?
mustn't we have stapled?
mustn't you have stapled?
mustn't they have stapled? 	mustn't I have been stapling?
mustn't you have been stapling?
mustn't he have been stapling?
mustn't we have been stapling?
mustn't you have been stapling?
mustn't they have been stapling?