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