straw that broke the camel's back字面意思压断骆驼脊梁的稻草，引申为压死骆驼的最后一根稻草；最后致命的一击。

【例句】
When the food came out cold, I decided it was the straw that broke the camel's back, and walked out.
当冷的食物被端出来后，我决定再也不忍受了，走了出去。

She's been dealing with these incidents for a long time and has been a faithful wife, but she's finally had enough, one source said. This one is the straw that broke the camel's back.
瓦妮莎一直疲于处理丈夫的这些花边新闻，她一直对丈夫忠心耿耿，但是现在她已经受够了，这件事简直是压死骆驼的最后一根稻草。