could file
Regular verb: file - filed- filed

Affirmation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could file
you could file
he could file
we could file
you could file
they could file 	I could be filing
you could be filing
he could be filing
we could be filing
you could be filing
they could be filing	I could have filed
you could have filed
he could have filed
we could have filed
you could have filed
they could have filed	I could have been filing
you could have been filing
he could have been filing
we could have been filing
you could have been filing
they could have been filing	

Negation 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
I could not file
you could not file
he could not file
we could not file
you could not file
they could not file 	I could not be filing
you could not be filing
he could not be filing
we could not be filing
you could not be filing
they could not be filing	I could not have filed
you could not have filed
he could not have filed
we could not have filed
you could not have filed
they could not have filed	I could not have been filing
you could not have been filing
he could not have been filing
we could not have been filing
you could not have been filing
they could not have been filing	

Interrogative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I file?
could you file?
could he file?
could we file?
could you file?
could they file? 	could I be filing?
could you be filing?
could he be filing?
could we be filing?
could you be filing?
could they be filing? 	could I have filed?
could you have filed?
could he have filed?
could we have filed?
could you have filed?
could they have filed? 	could I have been filing?
could you have been filing?
could he have been filing?
could we have been filing?
could you have been filing?
could they have been filing? 	

Interro-negative form 	
Simple form 	V-ing form 	Perfect 	V-ing perfect 	
could I not file?
could you not file?
could he not file?
could we not file?
could you not file?
could they not file? 	could I not be filing?
could you not be filing?
could he not be filing?
could we not be filing?
could you not be filing?
could they not be filing? 	could I not have filed?
could you not have filed?
could he not have filed?
could we not have filed?
could you not have filed?
could they not have filed? 	could I not have been filing?
could you not have been filing?
could he not have been filing?
could we not have been filing?
could you not have been filing?
could they not have been filing?