你孫外公 Your Grandpa Sun Is Here
師父定在他家了，你快上前。」行者罵道：「潑孽畜，你孫外公在這裡，送我師父出來，饒你命罷。」先鋒道：「大王，不好了，孫行者也尋將來了。」师父定在他家了，你快上前。」行者骂道：「泼孽畜，你孙外公在这里，送我师父出来，饶你命罢。」先锋道：「大王，不好了，孙行者也寻将来了。」
逐句解 Line by line
The master is certainly in his house. Get up there quickly."
Bajie's contribution to the assault is to point out where the danger is and invite somebody else to go first. 定在 is certainly-located-at, a flat statement of fact from a character who has no evidence for it and happens to be right.
Pilgrim shouted abuse: "You depraved beast! Your Grandpa Sun is standing right here. Send my master out and I will spare your life."
孫外公 is a joke the novel never tires of: 孫 is Wukong's surname and also the word for grandson, so calling himself somebody's grandfather while carrying that name is a pun that works in both directions at once. 罷 at the end is ba, the softening word that turns a threat into an offer.
The vanguard said, "Great King, this is bad. Sun the Pilgrim has come looking for us too."
The scout's assessment collapses in sixteen characters. 尋將來 for the third time in this chapter, the hollow 將 sitting between the verb and its direction and doing nothing but keeping the phrase in step.
The grandfather joke is one of the oldest in the book and it depends on a surname. Wukong is Sun, which in ordinary speech is the word for a grandson, so every time he announces himself as somebody's grandfather he is turning his own name inside out. It is roughly as if a man named Younger insisted on being addressed as sir.
The scene is built as a two-beat gag. The scout says there is nothing to worry about unless the hairy one turns up; the hairy one turns up. The fiends have now learned in the space of a page that their plan has attracted precisely the enemy they hoped it would not.