English verb conjugation
COULD XEROX

Regular verb: xerox - xeroxed - xeroxed

Affirmation

Simple form	V-ing form
I could xerox you could xerox he could xerox we could xerox you could xerox they could xerox	I could be xeroxing you could be xeroxing he could be xeroxing we could be xeroxing you could be xeroxing they could be xeroxing
Perfect	V-ing perfect
I could have xeroxed you could have xeroxed he could have xeroxed we could have xeroxed you could have xeroxed they could have xeroxed	I could have been xeroxing you could have been xeroxing he could have been xeroxing we could have been xeroxing you could have been xeroxing they could have been xeroxing

Negation

Simple form	V-ing form
I could not xerox you could not xerox he could not xerox we could not xerox you could not xerox they could not xerox	I could not be xeroxing you could not be xeroxing he could not be xeroxing we could not be xeroxing you could not be xeroxing they could not be xeroxing
Perfect	V-ing perfect
I could not have xeroxed you could not have xeroxed he could not have xeroxed we could not have xeroxed you could not have xeroxed they could not have xeroxed	I could not have been xeroxing you could not have been xeroxing he could not have been xeroxing we could not have been xeroxing you could not have been xeroxing they could not have been xeroxing

Interrogative form

Simple form	V-ing form
could I xerox? could you xerox? could he xerox? could we xerox? could you xerox? could they xerox?	could I be xeroxing? could you be xeroxing? could he be xeroxing? could we be xeroxing? could you be xeroxing? could they be xeroxing?
Perfect	V-ing perfect
could I have xeroxed? could you have xeroxed? could he have xeroxed? could we have xeroxed? could you have xeroxed? could they have xeroxed?	could I have been xeroxing? could you have been xeroxing? could he have been xeroxing? could we have been xeroxing? could you have been xeroxing? could they have been xeroxing?

Interro-negative form

Simple form	V-ing form
could I not xerox? could you not xerox? could he not xerox? could we not xerox? could you not xerox? could they not xerox?	could I not be xeroxing? could you not be xeroxing? could he not be xeroxing? could we not be xeroxing? could you not be xeroxing? could they not be xeroxing?
Perfect	V-ing perfect
could I not have xeroxed? could you not have xeroxed? could he not have xeroxed? could we not have xeroxed? could you not have xeroxed? could they not have xeroxed?	could I not have been xeroxing? could you not have been xeroxing? could he not have been xeroxing? could we not have been xeroxing? could you not have been xeroxing? could they not have been xeroxing?