I can sack you can sack she can sack we can sack you can sack they can sack
V-ing form
I can be sacking you can be sacking she can be sacking we can be sacking you can be sacking they can be sacking
Perfect
I can have sacked you can have sacked she can have sacked we can have sacked you can have sacked they can have sacked
V-ing perfect
I can have been sacking you can have been sacking she can have been sacking we can have been sacking you can have been sacking they can have been sacking
Negation
Simple form
I can't sack you can't sack she can't sack we can't sack you can't sack they can't sack
V-ing form
I can't be sacking you can't be sacking she can't be sacking we can't be sacking you can't be sacking they can't be sacking
Perfect
I can't have sacked you can't have sacked she can't have sacked we can't have sacked you can't have sacked they can't have sacked
V-ing perfect
I can't have been sacking you can't have been sacking she can't have been sacking we can't have been sacking you can't have been sacking they can't have been sacking
Interrogative form
Simple form
can I sack? can you sack? can she sack? can we sack? can you sack? can they sack?
V-ing form
can I be sacking? can you be sacking? can she be sacking? can we be sacking? can you be sacking? can they be sacking?
Perfect
can I have sacked? can you have sacked? can she have sacked? can we have sacked? can you have sacked? can they have sacked?
V-ing perfect
can I have been sacking? can you have been sacking? can she have been sacking? can we have been sacking? can you have been sacking? can they have been sacking?
Interro-negative form
Simple form
can't I sack? can't you sack? can't she sack? can't we sack? can't you sack? can't they sack?
V-ing form
can't I be sacking? can't you be sacking? can't she be sacking? can't we be sacking? can't you be sacking? can't they be sacking?
Perfect
can't I have sacked? can't you have sacked? can't she have sacked? can't we have sacked? can't you have sacked? can't they have sacked?
V-ing perfect
can't I have been sacking? can't you have been sacking? can't she have been sacking? can't we have been sacking? can't you have been sacking? can't they have been sacking?