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