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