I could highlight you could highlight she could highlight we could highlight you could highlight they could highlight
V-ing form
I could be highlighting you could be highlighting she could be highlighting we could be highlighting you could be highlighting they could be highlighting
Perfect
I could have highlighted you could have highlighted she could have highlighted we could have highlighted you could have highlighted they could have highlighted
V-ing perfect
I could have been highlighting you could have been highlighting she could have been highlighting we could have been highlighting you could have been highlighting they could have been highlighting
Negation
Simple form
I could not highlight you could not highlight she could not highlight we could not highlight you could not highlight they could not highlight
V-ing form
I could not be highlighting you could not be highlighting she could not be highlighting we could not be highlighting you could not be highlighting they could not be highlighting
Perfect
I could not have highlighted you could not have highlighted she could not have highlighted we could not have highlighted you could not have highlighted they could not have highlighted
V-ing perfect
I could not have been highlighting you could not have been highlighting she could not have been highlighting we could not have been highlighting you could not have been highlighting they could not have been highlighting
Interrogative form
Simple form
could I highlight? could you highlight? could she highlight? could we highlight? could you highlight? could they highlight?
V-ing form
could I be highlighting? could you be highlighting? could she be highlighting? could we be highlighting? could you be highlighting? could they be highlighting?
Perfect
could I have highlighted? could you have highlighted? could she have highlighted? could we have highlighted? could you have highlighted? could they have highlighted?
V-ing perfect
could I have been highlighting? could you have been highlighting? could she have been highlighting? could we have been highlighting? could you have been highlighting? could they have been highlighting?
Interro-negative form
Simple form
could I not highlight? could you not highlight? could she not highlight? could we not highlight? could you not highlight? could they not highlight?
V-ing form
could I not be highlighting? could you not be highlighting? could she not be highlighting? could we not be highlighting? could you not be highlighting? could they not be highlighting?
Perfect
could I not have highlighted? could you not have highlighted? could she not have highlighted? could we not have highlighted? could you not have highlighted? could they not have highlighted?
V-ing perfect
could I not have been highlighting? could you not have been highlighting? could she not have been highlighting? could we not have been highlighting? could you not have been highlighting? could they not have been highlighting?