I could halt you could halt he could halt we could halt you could halt they could halt
V-ing form
I could be halting you could be halting he could be halting we could be halting you could be halting they could be halting
Perfect
I could have halted you could have halted he could have halted we could have halted you could have halted they could have halted
V-ing perfect
I could have been halting you could have been halting he could have been halting we could have been halting you could have been halting they could have been halting
Negation
Simple form
I could not halt you could not halt he could not halt we could not halt you could not halt they could not halt
V-ing form
I could not be halting you could not be halting he could not be halting we could not be halting you could not be halting they could not be halting
Perfect
I could not have halted you could not have halted he could not have halted we could not have halted you could not have halted they could not have halted
V-ing perfect
I could not have been halting you could not have been halting he could not have been halting we could not have been halting you could not have been halting they could not have been halting
Interrogative form
Simple form
could I halt? could you halt? could he halt? could we halt? could you halt? could they halt?
V-ing form
could I be halting? could you be halting? could he be halting? could we be halting? could you be halting? could they be halting?
Perfect
could I have halted? could you have halted? could he have halted? could we have halted? could you have halted? could they have halted?
V-ing perfect
could I have been halting? could you have been halting? could he have been halting? could we have been halting? could you have been halting? could they have been halting?
Interro-negative form
Simple form
could I not halt? could you not halt? could he not halt? could we not halt? could you not halt? could they not halt?
V-ing form
could I not be halting? could you not be halting? could he not be halting? could we not be halting? could you not be halting? could they not be halting?
Perfect
could I not have halted? could you not have halted? could he not have halted? could we not have halted? could you not have halted? could they not have halted?
V-ing perfect
could I not have been halting? could you not have been halting? could he not have been halting? could we not have been halting? could you not have been halting? could they not have been halting?