I could harm you could harm she could harm we could harm you could harm they could harm
V-ing form
I could be harming you could be harming she could be harming we could be harming you could be harming they could be harming
Perfect
I could have harmed you could have harmed she could have harmed we could have harmed you could have harmed they could have harmed
V-ing perfect
I could have been harming you could have been harming she could have been harming we could have been harming you could have been harming they could have been harming
Negation
Simple form
I couldn't harm you couldn't harm she couldn't harm we couldn't harm you couldn't harm they couldn't harm
V-ing form
I couldn't be harming you couldn't be harming she couldn't be harming we couldn't be harming you couldn't be harming they couldn't be harming
Perfect
I couldn't have harmed you couldn't have harmed she couldn't have harmed we couldn't have harmed you couldn't have harmed they couldn't have harmed
V-ing perfect
I couldn't have been harming you couldn't have been harming she couldn't have been harming we couldn't have been harming you couldn't have been harming they couldn't have been harming
Interrogative form
Simple form
could I harm? could you harm? could she harm? could we harm? could you harm? could they harm?
V-ing form
could I be harming? could you be harming? could she be harming? could we be harming? could you be harming? could they be harming?
Perfect
could I have harmed? could you have harmed? could she have harmed? could we have harmed? could you have harmed? could they have harmed?
V-ing perfect
could I have been harming? could you have been harming? could she have been harming? could we have been harming? could you have been harming? could they have been harming?
Interro-negative form
Simple form
couldn't I harm? couldn't you harm? couldn't she harm? couldn't we harm? couldn't you harm? couldn't they harm?
V-ing form
couldn't I be harming? couldn't you be harming? couldn't she be harming? couldn't we be harming? couldn't you be harming? couldn't they be harming?
Perfect
couldn't I have harmed? couldn't you have harmed? couldn't she have harmed? couldn't we have harmed? couldn't you have harmed? couldn't they have harmed?
V-ing perfect
couldn't I have been harming? couldn't you have been harming? couldn't she have been harming? couldn't we have been harming? couldn't you have been harming? couldn't they have been harming?