睡不著 He Could Not Get to Sleep
惟行者有心闖禍,偏他睡不著,伸過手,將八戒腿上一捻。那獃子縮了腳,口裡哼哼的道:「睡了罷,辛辛苦苦的,有甚麼心腸還捻手捻腳的耍子?」惟行者有心闯祸,偏他睡不着,伸过手,将八戒腿上一捻。那呆子缩了脚,口里哼哼的道:「睡了罢,辛辛苦苦的,有甚么心肠还捻手捻脚的耍子?」
逐句解 Line by line
Only Pilgrim, with mischief on his mind, could not get to sleep; he reached over and gave Bajie's leg a pinch.
A small piece of machinery worth watching. 著 is zháo, falling asleep — and because that reading rises where the character's ordinary one falls, the 不 in front of it takes bù rather than the bú it would take before a falling tone. Two characters, and each decides the other. 有心闖禍 is having a mind to make trouble, deliberately courting it.
The Idiot pulled his leg back and grumbled: "Go to sleep. We are worn out — what sort of heart have you got, still pinching and poking about for fun?"
捻手捻腳 doubles the verb across hand and foot, so it is fiddling and prodding rather than one pinch. 耍子 is playing about, larking, and its last character takes the everyday zi. 罷 is ba, the suggesting particle: go on and sleep.
Three of them are asleep and the fourth is bored. Every disaster in the rest of this chapter follows from that, and the novel says so outright — mischief on his mind, courting trouble.
Bajie's complaint is the reasonable one and it will be ignored. He has spent the chapter being wrong about strategy and right about what is needed at the time, and this is the last and most costly instance.