I could detail you could detail he could detail we could detail you could detail they could detail
V-ing form
I could be detailing you could be detailing he could be detailing we could be detailing you could be detailing they could be detailing
Perfect
I could have detailed you could have detailed he could have detailed we could have detailed you could have detailed they could have detailed
V-ing perfect
I could have been detailing you could have been detailing he could have been detailing we could have been detailing you could have been detailing they could have been detailing
Negation
Simple form
I couldn't detail you couldn't detail he couldn't detail we couldn't detail you couldn't detail they couldn't detail
V-ing form
I couldn't be detailing you couldn't be detailing he couldn't be detailing we couldn't be detailing you couldn't be detailing they couldn't be detailing
Perfect
I couldn't have detailed you couldn't have detailed he couldn't have detailed we couldn't have detailed you couldn't have detailed they couldn't have detailed
V-ing perfect
I couldn't have been detailing you couldn't have been detailing he couldn't have been detailing we couldn't have been detailing you couldn't have been detailing they couldn't have been detailing
Interrogative form
Simple form
could I detail? could you detail? could he detail? could we detail? could you detail? could they detail?
V-ing form
could I be detailing? could you be detailing? could he be detailing? could we be detailing? could you be detailing? could they be detailing?
Perfect
could I have detailed? could you have detailed? could he have detailed? could we have detailed? could you have detailed? could they have detailed?
V-ing perfect
could I have been detailing? could you have been detailing? could he have been detailing? could we have been detailing? could you have been detailing? could they have been detailing?
Interro-negative form
Simple form
couldn't I detail? couldn't you detail? couldn't he detail? couldn't we detail? couldn't you detail? couldn't they detail?
V-ing form
couldn't I be detailing? couldn't you be detailing? couldn't he be detailing? couldn't we be detailing? couldn't you be detailing? couldn't they be detailing?
Perfect
couldn't I have detailed? couldn't you have detailed? couldn't he have detailed? couldn't we have detailed? couldn't you have detailed? couldn't they have detailed?
V-ing perfect
couldn't I have been detailing? couldn't you have been detailing? couldn't he have been detailing? couldn't we have been detailing? couldn't you have been detailing? couldn't they have been detailing?