I could retort you could retort he could retort we could retort you could retort they could retort
V-ing form
I could be retorting you could be retorting he could be retorting we could be retorting you could be retorting they could be retorting
Perfect
I could have retorted you could have retorted he could have retorted we could have retorted you could have retorted they could have retorted
V-ing perfect
I could have been retorting you could have been retorting he could have been retorting we could have been retorting you could have been retorting they could have been retorting
Negation
Simple form
I could not retort you could not retort he could not retort we could not retort you could not retort they could not retort
V-ing form
I could not be retorting you could not be retorting he could not be retorting we could not be retorting you could not be retorting they could not be retorting
Perfect
I could not have retorted you could not have retorted he could not have retorted we could not have retorted you could not have retorted they could not have retorted
V-ing perfect
I could not have been retorting you could not have been retorting he could not have been retorting we could not have been retorting you could not have been retorting they could not have been retorting
Interrogative form
Simple form
could I retort? could you retort? could he retort? could we retort? could you retort? could they retort?
V-ing form
could I be retorting? could you be retorting? could he be retorting? could we be retorting? could you be retorting? could they be retorting?
Perfect
could I have retorted? could you have retorted? could he have retorted? could we have retorted? could you have retorted? could they have retorted?
V-ing perfect
could I have been retorting? could you have been retorting? could he have been retorting? could we have been retorting? could you have been retorting? could they have been retorting?
Interro-negative form
Simple form
could I not retort? could you not retort? could he not retort? could we not retort? could you not retort? could they not retort?
V-ing form
could I not be retorting? could you not be retorting? could he not be retorting? could we not be retorting? could you not be retorting? could they not be retorting?
Perfect
could I not have retorted? could you not have retorted? could he not have retorted? could we not have retorted? could you not have retorted? could they not have retorted?
V-ing perfect
could I not have been retorting? could you not have been retorting? could he not have been retorting? could we not have been retorting? could you not have been retorting? could they not have been retorting?