沒個蒼蠅 Not A Fly In Years
老魔道:「兄弟們仔細。我這洞裡,遞年家沒個蒼蠅,但是有蒼蠅進來,就是孫行者。」行者暗笑道:「就變個蒼蠅諕他一諕,好開門。」大聖閃在傍邊,伸手去腦後拔了一根毫毛,吹一口仙氣,叫:「變!」老魔道:「兄弟们仔细。我这洞里,递年家没个苍蝇,但是有苍蝇进来,就是孙行者。」行者暗笑道:「就变个苍蝇諕他一諕,好开门。」大圣闪在傍边,伸手去脑后拔了一根毫毛,吹一口仙气,叫:「变!」
逐句解 Line by line
The old fiend said, "Brothers, be careful.
仔細 is zǐ xì. The word is really 子細, fine-as-a-seed, and the dictionary files it under 子 while noting that the vulgar spelling puts the man-radical on it. Thirteen of the fifteen sealed sites read zǐ; the two that do not are known errors awaiting repair.
In this cave of mine there hasn't been a fly in years. If a fly gets in, it is Sun Wukong."
遞年家 is vernacular for year after year, with 家 as a bare suffix carrying no household in it at all. And the boast is not idle — a cave that butchers people and has no flies is a cave under serious management.
Wukong laughed to himself. "Then I'll turn into a fly and give him a scare, and the doors will open."
The same doubling as before, 諕他一諕, and the same two rulings riding together: 諕 is xià, and the 一 in front of it has to become yí to sit before a fourth tone.
The Great Sage slipped aside, reached behind his head, plucked out a hair, blew a breath of immortal air on it and cried, "Change!"
傍 is páng, the side — the same character as 旁 and nothing to do with the bàng that means to lean on. The hair-plucking is Wukong's oldest and most domestic bit of magic, and the book still spends five verbs on it — slip aside, reach back, pull, blow, cry out — every single time.
The old fiend has just handed Wukong a perfect detection rule and a perfect vulnerability in the same breath. No flies means any fly is Sun Wukong — which is true, and which means Sun Wukong can now terrify this room by being a fly. The demon has built a tripwire and told the intruder where it is.
There is a real principle underneath the comedy. All three chiefs are competent; what beats them is that they keep announcing their reasoning out loud in front of the person it is about. Wukong's advantage in this whole scene is never power. It is that he is the only one in the room who knows what the room contains.