may countermand
Regular verb: countermand - countermanded- countermanded

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I may countermand
you may countermand
he may countermand
we may countermand
you may countermand
they may countermand 	I may be countermanding
you may be countermanding
he may be countermanding
we may be countermanding
you may be countermanding
they may be countermanding	I may have countermanded
you may have countermanded
he may have countermanded
we may have countermanded
you may have countermanded
they may have countermanded	I may have been countermanding
you may have been countermanding
he may have been countermanding
we may have been countermanding
you may have been countermanding
they may have been countermanding	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I mayn't countermand
you mayn't countermand
he mayn't countermand
we mayn't countermand
you mayn't countermand
they mayn't countermand 	I mayn't be countermanding
you mayn't be countermanding
he mayn't be countermanding
we mayn't be countermanding
you mayn't be countermanding
they mayn't be countermanding	I mayn't have countermanded
you mayn't have countermanded
he mayn't have countermanded
we mayn't have countermanded
you mayn't have countermanded
they mayn't have countermanded	I mayn't have been countermanding
you mayn't have been countermanding
he mayn't have been countermanding
we mayn't have been countermanding
you mayn't have been countermanding
they mayn't have been countermanding	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
may I countermand?
may you countermand?
may he countermand?
may we countermand?
may you countermand?
may they countermand? 	may I be countermanding?
may you be countermanding?
may he be countermanding?
may we be countermanding?
may you be countermanding?
may they be countermanding? 	may I have countermanded?
may you have countermanded?
may he have countermanded?
may we have countermanded?
may you have countermanded?
may they have countermanded? 	may I have been countermanding?
may you have been countermanding?
may he have been countermanding?
may we have been countermanding?
may you have been countermanding?
may they have been countermanding? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
mayn't I countermand?
mayn't you countermand?
mayn't he countermand?
mayn't we countermand?
mayn't you countermand?
mayn't they countermand? 	mayn't I be countermanding?
mayn't you be countermanding?
mayn't he be countermanding?
mayn't we be countermanding?
mayn't you be countermanding?
mayn't they be countermanding? 	mayn't I have countermanded?
mayn't you have countermanded?
mayn't he have countermanded?
mayn't we have countermanded?
mayn't you have countermanded?
mayn't they have countermanded? 	mayn't I have been countermanding?
mayn't you have been countermanding?
mayn't he have been countermanding?
mayn't we have been countermanding?
mayn't you have been countermanding?
mayn't they have been countermanding?