may grumble
Regular verb: grumble - grumbled- grumbled

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I may grumble
you may grumble
she may grumble
we may grumble
you may grumble
they may grumble 	I may be grumbling
you may be grumbling
she may be grumbling
we may be grumbling
you may be grumbling
they may be grumbling	I may have grumbled
you may have grumbled
she may have grumbled
we may have grumbled
you may have grumbled
they may have grumbled	I may have been grumbling
you may have been grumbling
she may have been grumbling
we may have been grumbling
you may have been grumbling
they may have been grumbling	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I mayn't grumble
you mayn't grumble
she mayn't grumble
we mayn't grumble
you mayn't grumble
they mayn't grumble 	I mayn't be grumbling
you mayn't be grumbling
she mayn't be grumbling
we mayn't be grumbling
you mayn't be grumbling
they mayn't be grumbling	I mayn't have grumbled
you mayn't have grumbled
she mayn't have grumbled
we mayn't have grumbled
you mayn't have grumbled
they mayn't have grumbled	I mayn't have been grumbling
you mayn't have been grumbling
she mayn't have been grumbling
we mayn't have been grumbling
you mayn't have been grumbling
they mayn't have been grumbling	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
may I grumble?
may you grumble?
may she grumble?
may we grumble?
may you grumble?
may they grumble? 	may I be grumbling?
may you be grumbling?
may she be grumbling?
may we be grumbling?
may you be grumbling?
may they be grumbling? 	may I have grumbled?
may you have grumbled?
may she have grumbled?
may we have grumbled?
may you have grumbled?
may they have grumbled? 	may I have been grumbling?
may you have been grumbling?
may she have been grumbling?
may we have been grumbling?
may you have been grumbling?
may they have been grumbling? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
mayn't I grumble?
mayn't you grumble?
mayn't she grumble?
mayn't we grumble?
mayn't you grumble?
mayn't they grumble? 	mayn't I be grumbling?
mayn't you be grumbling?
mayn't she be grumbling?
mayn't we be grumbling?
mayn't you be grumbling?
mayn't they be grumbling? 	mayn't I have grumbled?
mayn't you have grumbled?
mayn't she have grumbled?
mayn't we have grumbled?
mayn't you have grumbled?
mayn't they have grumbled? 	mayn't I have been grumbling?
mayn't you have been grumbling?
mayn't she have been grumbling?
mayn't we have been grumbling?
mayn't you have been grumbling?
mayn't they have been grumbling?