"I only know if things had gone his way, he would have killed two birds with one stone."
We kill several birds with one stone here, my friend.
I see a way to kill two birds with one stone here.
If they could kill two birds with one stone, then why not three?
Well, now we can kill two birds with one stone.
He was trying to kill two birds with one stone.
Seems like we can kill two birds with one stone.
He would kill two birds with one stone and also see what the girl was up to.
They killed more than 200 birds, or 139 over their limit.
But this way we have a chance to kill two birds with one stone.