1. Number one 最重要的人(或事物);最好的人(或事物)

e.g.: Many people consider themselves number one, the most important person.

很多人認為他們自己就是最好的，是最重要的一個人。

2. Look out for/Take care of number one 先為自己著想，照顧自己的利益，為自己打算

One and only 絕無僅有的;獨一無二的;有名的

e.g.: They are always looking out for number one and taking care of number one. It is as if they are the one and only person on Earth.

他們總是先為自己著想，只關心自己的利益，就好像他們是地球上唯一的人。

3. Pull a fast one 欺騙，搗鬼

e.g.: Jim only won the game because he pulled a fast one on his opponent.

吉姆因為跟對手耍了手段，才贏了比賽。

4. One in a million百萬分之一，鳳毛麟角，百里挑一，佼佼者

e.g.: She’s one in a million.

她是個百里挑一的人。

5. At one time 同時，曾經

e.g.: At one time we met frequently.

我們過去常見面。

6. Roll up into one 合為一體;兼于一身

e.g.: She is a great person -- kind, thoughtful and intelligent-- all good qualities rolled up into one.

她是個很優秀的女人——善良，體貼，聰慧——集所有可貴品質于一身。

7. One good turn deserves another. 善須善報;要以德報德;好人應得好報。

eg: If he does you a favor, you should do him a favor. One good turn deserves another.

如果他幫你的忙，那么你就應幫他的忙，以德報德嘛。

8. Be/go back to squareone 退回起點，從頭再來

e.g.: His papers were lost in the accident, so he had to go back to square one with the work.

他的論文在這次事故中弄丟了，只得從頭再寫。