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