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