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