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