may volunteer
Regular verb: volunteer - volunteered- volunteered

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I may volunteer
you may volunteer
he may volunteer
we may volunteer
you may volunteer
they may volunteer 	I may be volunteering
you may be volunteering
he may be volunteering
we may be volunteering
you may be volunteering
they may be volunteering	I may have volunteered
you may have volunteered
he may have volunteered
we may have volunteered
you may have volunteered
they may have volunteered	I may have been volunteering
you may have been volunteering
he may have been volunteering
we may have been volunteering
you may have been volunteering
they may have been volunteering	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I mayn't volunteer
you mayn't volunteer
he mayn't volunteer
we mayn't volunteer
you mayn't volunteer
they mayn't volunteer 	I mayn't be volunteering
you mayn't be volunteering
he mayn't be volunteering
we mayn't be volunteering
you mayn't be volunteering
they mayn't be volunteering	I mayn't have volunteered
you mayn't have volunteered
he mayn't have volunteered
we mayn't have volunteered
you mayn't have volunteered
they mayn't have volunteered	I mayn't have been volunteering
you mayn't have been volunteering
he mayn't have been volunteering
we mayn't have been volunteering
you mayn't have been volunteering
they mayn't have been volunteering	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
may I volunteer?
may you volunteer?
may he volunteer?
may we volunteer?
may you volunteer?
may they volunteer? 	may I be volunteering?
may you be volunteering?
may he be volunteering?
may we be volunteering?
may you be volunteering?
may they be volunteering? 	may I have volunteered?
may you have volunteered?
may he have volunteered?
may we have volunteered?
may you have volunteered?
may they have volunteered? 	may I have been volunteering?
may you have been volunteering?
may he have been volunteering?
may we have been volunteering?
may you have been volunteering?
may they have been volunteering? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
mayn't I volunteer?
mayn't you volunteer?
mayn't he volunteer?
mayn't we volunteer?
mayn't you volunteer?
mayn't they volunteer? 	mayn't I be volunteering?
mayn't you be volunteering?
mayn't he be volunteering?
mayn't we be volunteering?
mayn't you be volunteering?
mayn't they be volunteering? 	mayn't I have volunteered?
mayn't you have volunteered?
mayn't he have volunteered?
mayn't we have volunteered?
mayn't you have volunteered?
mayn't they have volunteered? 	mayn't I have been volunteering?
mayn't you have been volunteering?
mayn't he have been volunteering?
mayn't we have been volunteering?
mayn't you have been volunteering?
mayn't they have been volunteering?