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