I may grumble you may grumble she may grumble we may grumble you may grumble they may grumble
V-ing form
I may be grumbling you may be grumbling she may be grumbling we may be grumbling you may be grumbling they may be grumbling
Perfect
I may have grumbled you may have grumbled she may have grumbled we may have grumbled you may have grumbled they may have grumbled
V-ing perfect
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
I may not grumble you may not grumble she may not grumble we may not grumble you may not grumble they may not grumble
V-ing form
I may not be grumbling you may not be grumbling she may not be grumbling we may not be grumbling you may not be grumbling they may not be grumbling
Perfect
I may not have grumbled you may not have grumbled she may not have grumbled we may not have grumbled you may not have grumbled they may not have grumbled
V-ing perfect
I may not have been grumbling you may not have been grumbling she may not have been grumbling we may not have been grumbling you may not have been grumbling they may not have been grumbling
Interrogative form
Simple form
may I grumble? may you grumble? may she grumble? may we grumble? may you grumble? may they grumble?
V-ing form
may I be grumbling? may you be grumbling? may she be grumbling? may we be grumbling? may you be grumbling? may they be grumbling?
Perfect
may I have grumbled? may you have grumbled? may she have grumbled? may we have grumbled? may you have grumbled? may they have grumbled?
V-ing perfect
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
may I not grumble? may you not grumble? may she not grumble? may we not grumble? may you not grumble? may they not grumble?
V-ing form
may I not be grumbling? may you not be grumbling? may she not be grumbling? may we not be grumbling? may you not be grumbling? may they not be grumbling?
Perfect
may I not have grumbled? may you not have grumbled? may she not have grumbled? may we not have grumbled? may you not have grumbled? may they not have grumbled?
V-ing perfect
may I not have been grumbling? may you not have been grumbling? may she not have been grumbling? may we not have been grumbling? may you not have been grumbling? may they not have been grumbling?