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