句型解说：
pretended dislike for something unobtainable
对于得不到的东西装作不喜欢
也就是我们常说“吃不到葡萄，就说葡萄是酸的”。

灵活运用：
When she said the performance was terrible ,it was only sour grapes because she auditioned for the show but wasn't accepted．
她说这个表演很差完全是酸葡萄作用，因为她应征此项演出而未被录用。