English verb conjugation
CAN COUNTERMAND

Regular verb: countermand - countermanded - countermanded

Affirmation

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

Negation

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

Interrogative form

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

Interro-negative form

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