English verb conjugation
COULD CONCUSS

Regular verb: concuss - concussed - concussed

Affirmation

Simple form	V-ing form
I could concuss you could concuss he could concuss we could concuss you could concuss they could concuss	I could be concussing you could be concussing he could be concussing we could be concussing you could be concussing they could be concussing
Perfect	V-ing perfect
I could have concussed you could have concussed he could have concussed we could have concussed you could have concussed they could have concussed	I could have been concussing you could have been concussing he could have been concussing we could have been concussing you could have been concussing they could have been concussing

Negation

Simple form	V-ing form
I could not concuss you could not concuss he could not concuss we could not concuss you could not concuss they could not concuss	I could not be concussing you could not be concussing he could not be concussing we could not be concussing you could not be concussing they could not be concussing
Perfect	V-ing perfect
I could not have concussed you could not have concussed he could not have concussed we could not have concussed you could not have concussed they could not have concussed	I could not have been concussing you could not have been concussing he could not have been concussing we could not have been concussing you could not have been concussing they could not have been concussing

Interrogative form

Simple form	V-ing form
could I concuss? could you concuss? could he concuss? could we concuss? could you concuss? could they concuss?	could I be concussing? could you be concussing? could he be concussing? could we be concussing? could you be concussing? could they be concussing?
Perfect	V-ing perfect
could I have concussed? could you have concussed? could he have concussed? could we have concussed? could you have concussed? could they have concussed?	could I have been concussing? could you have been concussing? could he have been concussing? could we have been concussing? could you have been concussing? could they have been concussing?

Interro-negative form

Simple form	V-ing form
could I not concuss? could you not concuss? could he not concuss? could we not concuss? could you not concuss? could they not concuss?	could I not be concussing? could you not be concussing? could he not be concussing? could we not be concussing? could you not be concussing? could they not be concussing?
Perfect	V-ing perfect
could I not have concussed? could you not have concussed? could he not have concussed? could we not have concussed? could you not have concussed? could they not have concussed?	could I not have been concussing? could you not have been concussing? could he not have been concussing? could we not have been concussing? could you not have been concussing? could they not have been concussing?