I could sack you could sack he could sack we could sack you could sack they could sack
V-ing form
I could be sacking you could be sacking he could be sacking we could be sacking you could be sacking they could be sacking
Perfect
I could have sacked you could have sacked he could have sacked we could have sacked you could have sacked they could have sacked
V-ing perfect
I could have been sacking you could have been sacking he could have been sacking we could have been sacking you could have been sacking they could have been sacking
Negation
Simple form
I could not sack you could not sack he could not sack we could not sack you could not sack they could not sack
V-ing form
I could not be sacking you could not be sacking he could not be sacking we could not be sacking you could not be sacking they could not be sacking
Perfect
I could not have sacked you could not have sacked he could not have sacked we could not have sacked you could not have sacked they could not have sacked
V-ing perfect
I could not have been sacking you could not have been sacking he could not have been sacking we could not have been sacking you could not have been sacking they could not have been sacking
Interrogative form
Simple form
could I sack? could you sack? could he sack? could we sack? could you sack? could they sack?
V-ing form
could I be sacking? could you be sacking? could he be sacking? could we be sacking? could you be sacking? could they be sacking?
Perfect
could I have sacked? could you have sacked? could he have sacked? could we have sacked? could you have sacked? could they have sacked?
V-ing perfect
could I have been sacking? could you have been sacking? could he have been sacking? could we have been sacking? could you have been sacking? could they have been sacking?
Interro-negative form
Simple form
could I not sack? could you not sack? could he not sack? could we not sack? could you not sack? could they not sack?
V-ing form
could I not be sacking? could you not be sacking? could he not be sacking? could we not be sacking? could you not be sacking? could they not be sacking?
Perfect
could I not have sacked? could you not have sacked? could he not have sacked? could we not have sacked? could you not have sacked? could they not have sacked?
V-ing perfect
could I not have been sacking? could you not have been sacking? could he not have been sacking? could we not have been sacking? could you not have been sacking? could they not have been sacking?