咬斷索子 He Bites The Rope Through
行者四顧無人，將拑咬斷索子叫走。那獃子脫了手道：「哥哥，我的兵器被他收了，又奈何？」行者道：「你可知道收在那裡？」八戒道：「當被那怪拿上宮殿去了。」行者道：「你先去牌樓下等我。」八戒逃生，悄悄的溜出。行者四顾无人，将拑咬断索子叫走。那呆子脱了手道：「哥哥，我的兵器被他收了，又奈何？」行者道：「你可知道收在那里？」八戒道：「当被那怪拿上宫殿去了。」行者道：「你先去牌楼下等我。」八戒逃生，悄悄的溜出。
逐句解 Line by line
Pilgrim looked about and saw nobody, so with his pincers he bit the rope through and told him to run.
拑 qián is a pair of pincers, and the word is doing double duty: it is a crab's claw and it is the tool for the job. 將 is the disposal marker jiāng, taking the pincers as the instrument. 索子 keeps 子 at the neutral zi, the vernacular suffix.
The idiot got his hands free and said, "Brother, he has taken away my weapon. What is to be done?"
Two 了 in one segment and both are the perfective le. 奈何 is the classical what-is-to-be-done, and Eight Rules produces it in the middle of a vernacular complaint. 那 is deictic and 獃子 keeps the neutral zi.
Pilgrim said, "Do you know where it has been put?"
那裡 is nà here and not the interrogative nǎ, although the sentence is a question: what is being asked is whether he knows, and 收在那裡 is the place, deictically pointed at. The interrogative force sits in 可, not in 那.
Eight Rules said, "It was carried up to the palace hall by the fiend just then."
當 is dāng, at that time. 被 marks the passive again — the third in four segments, and every one of them has Eight Rules as the thing acted upon. 那 is deictic and 了 is the perfective le.
Pilgrim said, "You go on ahead and wait for me under the ceremonial arch."
No graph in this segment stands in any guard roster; every reading is the pypinyin default and every one is right. 牌樓 is the free-standing arch that marks an approach, and it has already served in this chapter as the point Pilgrim swam to on his way in.
Eight Rules fled for his life and slipped quietly out.
的 holds de by the invariant ruling, here in the adverbial frame 悄悄的. 逃生 is the same pair used of the two maimed fiends fleeing into the water at the start of the chapter and of the small fiends again in the battle rhapsody. It occurs four times in all, and this is the third.
The whole rescue takes six short exchanges and no magic beyond the disguise. He looks round, bites through the rope with a claw, and sends the prisoner off. What takes the time is not the escape but the weapon, and the conversation about it is conducted in whispers next to a pillar in an enemy palace.
Eight Rules will not leave without the rake, and the novel treats this as reasonable rather than comic. The question is practical — do you know where it was put — and the answer is exact: taken up to the hall. Neither of them suggests going without it.
The instrument matters. A crab has pincers, and the text uses the word for pincers rather than for claws, so that the tool and the disguise are the same object. Pilgrim did not bring a knife or use the cudgel; he used what the shape he had chosen already came with.