I could scroll you could scroll she could scroll we could scroll you could scroll they could scroll
V-ing form
I could be scrolling you could be scrolling she could be scrolling we could be scrolling you could be scrolling they could be scrolling
Perfect
I could have scrolled you could have scrolled she could have scrolled we could have scrolled you could have scrolled they could have scrolled
V-ing perfect
I could have been scrolling you could have been scrolling she could have been scrolling we could have been scrolling you could have been scrolling they could have been scrolling
Negation
Simple form
I could not scroll you could not scroll she could not scroll we could not scroll you could not scroll they could not scroll
V-ing form
I could not be scrolling you could not be scrolling she could not be scrolling we could not be scrolling you could not be scrolling they could not be scrolling
Perfect
I could not have scrolled you could not have scrolled she could not have scrolled we could not have scrolled you could not have scrolled they could not have scrolled
V-ing perfect
I could not have been scrolling you could not have been scrolling she could not have been scrolling we could not have been scrolling you could not have been scrolling they could not have been scrolling
Interrogative form
Simple form
could I scroll? could you scroll? could she scroll? could we scroll? could you scroll? could they scroll?
V-ing form
could I be scrolling? could you be scrolling? could she be scrolling? could we be scrolling? could you be scrolling? could they be scrolling?
Perfect
could I have scrolled? could you have scrolled? could she have scrolled? could we have scrolled? could you have scrolled? could they have scrolled?
V-ing perfect
could I have been scrolling? could you have been scrolling? could she have been scrolling? could we have been scrolling? could you have been scrolling? could they have been scrolling?
Interro-negative form
Simple form
could I not scroll? could you not scroll? could she not scroll? could we not scroll? could you not scroll? could they not scroll?
V-ing form
could I not be scrolling? could you not be scrolling? could she not be scrolling? could we not be scrolling? could you not be scrolling? could they not be scrolling?
Perfect
could I not have scrolled? could you not have scrolled? could she not have scrolled? could we not have scrolled? could you not have scrolled? could they not have scrolled?
V-ing perfect
could I not have been scrolling? could you not have been scrolling? could she not have been scrolling? could we not have been scrolling? could you not have been scrolling? could they not have been scrolling?