Sun Wukong's question was entirely a test for Zhu Bajie. Hearing Sun Wukong suddenly asking this, Zhu Bajie couldn't help but be stunned, then after thinking, said, "I can't remember, those are matters from who knows which past life, who keeps track of that anymore. But if you ask me whether Cuilan of Gao Laozhuang is beautiful, I surely know that, hehe!" Zhu Bajie's answer slightly relieved Sun Wukong because indeed only Zhu Bajie would answer in such a way. If Bajie were actually being impersonated by someone else, when Sun Wukong suddenly popped such a question, the imposter would have surely become suspicious.