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