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