could pioneer
Regular verb: pioneer - pioneered- pioneered

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could pioneer
you could pioneer
she could pioneer
we could pioneer
you could pioneer
they could pioneer 	I could be pioneering
you could be pioneering
she could be pioneering
we could be pioneering
you could be pioneering
they could be pioneering	I could have pioneered
you could have pioneered
she could have pioneered
we could have pioneered
you could have pioneered
they could have pioneered	I could have been pioneering
you could have been pioneering
she could have been pioneering
we could have been pioneering
you could have been pioneering
they could have been pioneering	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I couldn't pioneer
you couldn't pioneer
she couldn't pioneer
we couldn't pioneer
you couldn't pioneer
they couldn't pioneer 	I couldn't be pioneering
you couldn't be pioneering
she couldn't be pioneering
we couldn't be pioneering
you couldn't be pioneering
they couldn't be pioneering	I couldn't have pioneered
you couldn't have pioneered
she couldn't have pioneered
we couldn't have pioneered
you couldn't have pioneered
they couldn't have pioneered	I couldn't have been pioneering
you couldn't have been pioneering
she couldn't have been pioneering
we couldn't have been pioneering
you couldn't have been pioneering
they couldn't have been pioneering	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I pioneer?
could you pioneer?
could she pioneer?
could we pioneer?
could you pioneer?
could they pioneer? 	could I be pioneering?
could you be pioneering?
could she be pioneering?
could we be pioneering?
could you be pioneering?
could they be pioneering? 	could I have pioneered?
could you have pioneered?
could she have pioneered?
could we have pioneered?
could you have pioneered?
could they have pioneered? 	could I have been pioneering?
could you have been pioneering?
could she have been pioneering?
could we have been pioneering?
could you have been pioneering?
could they have been pioneering? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
couldn't I pioneer?
couldn't you pioneer?
couldn't she pioneer?
couldn't we pioneer?
couldn't you pioneer?
couldn't they pioneer? 	couldn't I be pioneering?
couldn't you be pioneering?
couldn't she be pioneering?
couldn't we be pioneering?
couldn't you be pioneering?
couldn't they be pioneering? 	couldn't I have pioneered?
couldn't you have pioneered?
couldn't she have pioneered?
couldn't we have pioneered?
couldn't you have pioneered?
couldn't they have pioneered? 	couldn't I have been pioneering?
couldn't you have been pioneering?
couldn't she have been pioneering?
couldn't we have been pioneering?
couldn't you have been pioneering?
couldn't they have been pioneering?