1 airhead =stupid person 笨蛋，傻瓜

　　e.g. Other people think she's an airhead, but to me she's a genius. 别人都认为她是个傻瓜，但我觉得她是个天才。

　　2 bust a gut =try extremely hard to do something 竭尽全力

　　In order to pass the exam with flying colours, I have to bust my gut. 为了高分通过考试，我不得不竭尽全力。

　　3 goof =make a silly mistake 犯愚蠢的错误

　　I thought that I would pass the exam with flying colours, but unfortunately I goofed in the exam and I feel lousy. 我原本以为我会高分通过考试，但不幸的是我考砸了，感觉很糟糕。

　　4 out of it =unable to think clearly because you are tired因为太累昏昏然的

　　I hadn't slept all night so when they called, I was totally out of it. 我整夜没合眼，所以他们给我打电话的时候，我都迷迷糊糊的。

　　5 random =surprising 惊人的，意外的

　　Hey, check this out! Potato cookies! That's so random! 嘿，快看这个！是土豆饼干！太让人吃惊了！

　　6 a rip-off =something that is overly expensive 过于昂贵的东西

　　The coat cost me 3000 dollars, which was a bit of a rip-off, and now I hardly ever wear it. What a waste! 那件外套花了我3000美元，真是贵的出奇。而且我现在几乎从来不穿，真是浪费。

　　7 take the piss out of sb. =to make fun 嘲笑，取弄

　　She really took the piss out of him. 我们好好奚落了他一番。

　　8 bring sb. up to speed on sth. =make sb. have the latest information or knowledge about sth. 跟上形势，了解最新情况

　　So he asked me if I could bring him up to speed on the situation. 所以他问我能否给他介绍一下最新情况。