I could saber you could saber he could saber we could saber you could saber they could saber
V-ing form
I could be sabering you could be sabering he could be sabering we could be sabering you could be sabering they could be sabering
Perfect
I could have sabered you could have sabered he could have sabered we could have sabered you could have sabered they could have sabered
V-ing perfect
I could have been sabering you could have been sabering he could have been sabering we could have been sabering you could have been sabering they could have been sabering
Negation
Simple form
I could not saber you could not saber he could not saber we could not saber you could not saber they could not saber
V-ing form
I could not be sabering you could not be sabering he could not be sabering we could not be sabering you could not be sabering they could not be sabering
Perfect
I could not have sabered you could not have sabered he could not have sabered we could not have sabered you could not have sabered they could not have sabered
V-ing perfect
I could not have been sabering you could not have been sabering he could not have been sabering we could not have been sabering you could not have been sabering they could not have been sabering
Interrogative form
Simple form
could I saber? could you saber? could he saber? could we saber? could you saber? could they saber?
V-ing form
could I be sabering? could you be sabering? could he be sabering? could we be sabering? could you be sabering? could they be sabering?
Perfect
could I have sabered? could you have sabered? could he have sabered? could we have sabered? could you have sabered? could they have sabered?
V-ing perfect
could I have been sabering? could you have been sabering? could he have been sabering? could we have been sabering? could you have been sabering? could they have been sabering?
Interro-negative form
Simple form
could I not saber? could you not saber? could he not saber? could we not saber? could you not saber? could they not saber?
V-ing form
could I not be sabering? could you not be sabering? could he not be sabering? could we not be sabering? could you not be sabering? could they not be sabering?
Perfect
could I not have sabered? could you not have sabered? could he not have sabered? could we not have sabered? could you not have sabered? could they not have sabered?
V-ing perfect
could I not have been sabering? could you not have been sabering? could he not have been sabering? could we not have been sabering? could you not have been sabering? could they not have been sabering?