1 on a cloud
On a cloud是很高興的意思，高興得走路輕飄飄，好像騰云駕霧一樣。
例如：I've been on a cloud all day long--I heard this morning that I got an A on my final biochemistry exam.
我今天一天都很高興，因為我早上聽說，我生化期末考試得了一個A。
又如：My wife has been on a cloud since I told her the other day I would spend my year-end bonus at the office to take us to Hawaii to celebrate our twentieth wedding anniversary. And to tell you the truth, I'm really looking forward to it myself.
我那天告訴我的妻子，我要把辦公室發(fā)給我的年終獎金用來和她一起去夏威夷旅行，以慶祝我們結婚二十周年。自從那天起，我太太一直很高興。說實話，我自己也非常想去。
2 under a cloud
任何人under a cloud是絕不會高興的，因為他不是丟盡了面子，就是被懷疑做了什么壞事。Under a cloud是丟面子、被懷疑的意思。
下面是一個人在講另外一個被逮捕的人，這人被指控和販毒有關：
The judge had to let him go because there wasn't enough evidence against him. But he's going around under a cloud because most people think he's guilty.
法官由于沒有足夠的證據來定罪，所以只好放了他。但是，他到哪兒都受懷疑，因為大多數人都認為他是有罪的。
又如：See that man sitting at the table by himself? He's supposed to be a very smart lawyer, but he's been under a cloud ever since he was mixed up in a scandal involving a company that was run by a mobster.
瞧那個桌子邊獨自坐著的人，看見嗎？他本來是一個很能干的律師，但是自從他和一個公司的丑聞有牽連以來，他一直被人懷疑，而那個公司是由流氓集團經營的。
3 in the clouds
我們每個人恐怕都有白日做夢的時候。有的時候，我們一邊走路，一邊在想心事，或者是一邊做什么事，一邊在想其他事情，身邊發(fā)生什么事全然沒有注意到。美國人把這叫做：in the clouds。In the clouds可以解釋為：心不在焉，思想開小差。
例如：Sally is my best friend but she walked right past me today, and didn't even say hello. Her head certainly was in the clouds--she looked like her mind was a thousand miles away.
沙莉是我最好的朋友，可是，她今天在我身旁走過，連招呼都沒有跟我打。她肯定在白日做夢，看起來她的心思好像在一千哩以外的地方。
又如：I was really embarrassed--the teacher asked me a question and I didn't even hear him; I was daydreaming and my head was in the clouds.
我當時真是非常難堪。老師問我問題，我根本沒有聽見。那時，我剛好在做白日夢，思想在開小差。
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