could xerox
Regular verb: xerox - xeroxed- xeroxed

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
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	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 	Perfect 	V-ing perfect 	
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	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 	Perfect 	V-ing perfect 	
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? 	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 	Perfect 	V-ing perfect 	
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? 	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?