I could whack you could whack he could whack we could whack you could whack they could whack
V-ing form
I could be whacking you could be whacking he could be whacking we could be whacking you could be whacking they could be whacking
Perfect
I could have whacked you could have whacked he could have whacked we could have whacked you could have whacked they could have whacked
V-ing perfect
I could have been whacking you could have been whacking he could have been whacking we could have been whacking you could have been whacking they could have been whacking
Negation
Simple form
I couldn't whack you couldn't whack he couldn't whack we couldn't whack you couldn't whack they couldn't whack
V-ing form
I couldn't be whacking you couldn't be whacking he couldn't be whacking we couldn't be whacking you couldn't be whacking they couldn't be whacking
Perfect
I couldn't have whacked you couldn't have whacked he couldn't have whacked we couldn't have whacked you couldn't have whacked they couldn't have whacked
V-ing perfect
I couldn't have been whacking you couldn't have been whacking he couldn't have been whacking we couldn't have been whacking you couldn't have been whacking they couldn't have been whacking
Interrogative form
Simple form
could I whack? could you whack? could he whack? could we whack? could you whack? could they whack?
V-ing form
could I be whacking? could you be whacking? could he be whacking? could we be whacking? could you be whacking? could they be whacking?
Perfect
could I have whacked? could you have whacked? could he have whacked? could we have whacked? could you have whacked? could they have whacked?
V-ing perfect
could I have been whacking? could you have been whacking? could he have been whacking? could we have been whacking? could you have been whacking? could they have been whacking?
Interro-negative form
Simple form
couldn't I whack? couldn't you whack? couldn't he whack? couldn't we whack? couldn't you whack? couldn't they whack?
V-ing form
couldn't I be whacking? couldn't you be whacking? couldn't he be whacking? couldn't we be whacking? couldn't you be whacking? couldn't they be whacking?
Perfect
couldn't I have whacked? couldn't you have whacked? couldn't he have whacked? couldn't we have whacked? couldn't you have whacked? couldn't they have whacked?
V-ing perfect
couldn't I have been whacking? couldn't you have been whacking? couldn't he have been whacking? couldn't we have been whacking? couldn't you have been whacking? couldn't they have been whacking?