out of the blue "突然"、“晴天霹雳”、“出乎意料”
1、It's kind of out of the blue that he is leaving tomorrow.
他明天就要离开，这来得有点突然。
2、Tom lost his job last week. Don't think it's out of the blue?
阿汤哥上周失业了。这太出乎人的意料了，不是吗？