6.On cloud nine 非常高兴，心情十分舒畅

形容一个人的心情好的不能再好了。

例句：

When the boss announced my promotion, I was on cloud nine.

当老板宣布我获得晋升时，我非常高兴。

7.To chase the rainbows 追逐彩虹，痴人说梦

形容一个人尽是想好事，而且是不太可能的事。

例句：

You have only started two months ago, you are already thinking about promotion. Well, I think you're just chasing rainbows.

你才来了两个月就想着升职的事情了，我看啊，你是净想好事儿呢。

8.Once in a blue moon 千载难逢地，百年不遇

形容非常罕见。

例句：

Brian has very little contact with his sister. They see each other once in a blue moon.

布莱恩和他姐姐没有什么联系。他们很少见面。

9.Every cloud has a silver lining 黑暗中总有一线光明

鼓励人们即使在最困难的时刻也不要失去信心或放弃希望。

例句：

Don't worry too much about your dropping out of university, every cloud has a silver lining.

大学辍学这事儿你也别太担忧，塞翁失马，焉知非福。

10.A fair-weather friend 可共安乐不能共患难的朋友

这和同甘共苦意思相反，指那些关键时刻靠不住的朋友。

例句：

I thought I could count on Sue, but I've discovered she's just a fair-weather friend.

我以为我能依赖苏这个人呢，不过，我发现她只不过是个只能同甘不能共苦的朋友。