could plug
Regular verb: plug - plugged- plugged

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could plug
you could plug
she could plug
we could plug
you could plug
they could plug 	I could be plugging
you could be plugging
she could be plugging
we could be plugging
you could be plugging
they could be plugging	I could have plugged
you could have plugged
she could have plugged
we could have plugged
you could have plugged
they could have plugged	I could have been plugging
you could have been plugging
she could have been plugging
we could have been plugging
you could have been plugging
they could have been plugging	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could not plug
you could not plug
she could not plug
we could not plug
you could not plug
they could not plug 	I could not be plugging
you could not be plugging
she could not be plugging
we could not be plugging
you could not be plugging
they could not be plugging	I could not have plugged
you could not have plugged
she could not have plugged
we could not have plugged
you could not have plugged
they could not have plugged	I could not have been plugging
you could not have been plugging
she could not have been plugging
we could not have been plugging
you could not have been plugging
they could not have been plugging	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I plug?
could you plug?
could she plug?
could we plug?
could you plug?
could they plug? 	could I be plugging?
could you be plugging?
could she be plugging?
could we be plugging?
could you be plugging?
could they be plugging? 	could I have plugged?
could you have plugged?
could she have plugged?
could we have plugged?
could you have plugged?
could they have plugged? 	could I have been plugging?
could you have been plugging?
could she have been plugging?
could we have been plugging?
could you have been plugging?
could they have been plugging? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I not plug?
could you not plug?
could she not plug?
could we not plug?
could you not plug?
could they not plug? 	could I not be plugging?
could you not be plugging?
could she not be plugging?
could we not be plugging?
could you not be plugging?
could they not be plugging? 	could I not have plugged?
could you not have plugged?
could she not have plugged?
could we not have plugged?
could you not have plugged?
could they not have plugged? 	could I not have been plugging?
could you not have been plugging?
could she not have been plugging?
could we not have been plugging?
could you not have been plugging?
could they not have been plugging?