could black
Regular verb: black - blacked- blacked

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could black
you could black
he could black
we could black
you could black
they could black 	I could be blacking
you could be blacking
he could be blacking
we could be blacking
you could be blacking
they could be blacking	I could have blacked
you could have blacked
he could have blacked
we could have blacked
you could have blacked
they could have blacked	I could have been blacking
you could have been blacking
he could have been blacking
we could have been blacking
you could have been blacking
they could have been blacking	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could not black
you could not black
he could not black
we could not black
you could not black
they could not black 	I could not be blacking
you could not be blacking
he could not be blacking
we could not be blacking
you could not be blacking
they could not be blacking	I could not have blacked
you could not have blacked
he could not have blacked
we could not have blacked
you could not have blacked
they could not have blacked	I could not have been blacking
you could not have been blacking
he could not have been blacking
we could not have been blacking
you could not have been blacking
they could not have been blacking	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I black?
could you black?
could he black?
could we black?
could you black?
could they black? 	could I be blacking?
could you be blacking?
could he be blacking?
could we be blacking?
could you be blacking?
could they be blacking? 	could I have blacked?
could you have blacked?
could he have blacked?
could we have blacked?
could you have blacked?
could they have blacked? 	could I have been blacking?
could you have been blacking?
could he have been blacking?
could we have been blacking?
could you have been blacking?
could they have been blacking? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I not black?
could you not black?
could he not black?
could we not black?
could you not black?
could they not black? 	could I not be blacking?
could you not be blacking?
could he not be blacking?
could we not be blacking?
could you not be blacking?
could they not be blacking? 	could I not have blacked?
could you not have blacked?
could he not have blacked?
could we not have blacked?
could you not have blacked?
could they not have blacked? 	could I not have been blacking?
could you not have been blacking?
could he not have been blacking?
could we not have been blacking?
could you not have been blacking?
could they not have been blacking?