另有個小洞 Another Little Cave Below
都只說：「這孽畜一定是早出了這洞，遠遠去哩。」那曉得他在那東南黑角落上，望下去，另有個小洞。都只说：「这孽畜一定是早出了这洞，远远去哩。」那晓得他在那东南黑角落上，望下去，另有个小洞。
逐句解 Line by line
They all said, "This creature must have got out of the cave early and gone a long way off."
孽畜 is a wicked beast, and it is the word for an animal that has done wrong rather than a demon that has. The army has settled on the wrong conclusion and is comfortable with it. 都 is dōu, all of them — nobody dissents.
How were they to know that away on the south-east, in a dark corner, if you looked down there was another little cave?
那 is nǎ here — how were they to know — the narrator's own aside, and it is the hinge of the chapter's last movement. 曉得 keeps 得 at dé, the ending for verbs of knowing. The discovery is handed to the reader before it is handed to anybody in the story, which is the oldest way of making a search unbearable to watch.
The narrator steps forward and gives the answer away, and the story is better for it. The army stands in a hundred and seventy kilometres of empty tunnel agreeing she has fled, and the reader can see the door they have missed.
The scale is the joke, and it has been the joke since the burrows were first counted. The whole of heaven has swept a country the size of a province and the master is behind a small door in a dark corner.