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