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