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