I'm on a diet.
我在节食。

My doctor ordered me a diet without sugar.
我的医生给我开了无糖食谱。

A: Would you like a bar of chocolate?
甲：要块巧克力吗？

B: No. Thank you. I'm on a diet.
乙：不，谢谢。我在节食。

A: Are you? You don't have to!
甲：是吗。你没必要节食呀！

B: I must. My doctor ordered me a diet without sugar.
乙：我得节食。我的医生给我开了无糖食谱。

(Catherine and Judy are talking on the plone about diet.)
（凯瑟琳和米蒂在打电话谈节食的事。）

Catherine: Hello.
凯瑟琳：喂。

Judy: Hello. Catherine?
朱蒂：喂，是凯瑟琳吗？

Catherine: Yeah. Is that Judy?
凯瑟琳：对。是朱蒂吗？

Judy: Right. Terrible! I can't wear the dress I bought a month ago.
朱蒂：对。真糟糕。上个月买的衣服又不能穿了。

Catherine: Are you talking about the one we bought together.
凯瑟琳：你是在说我们上次一起买的那件吗？

Judy: Yeah, It's already tight. I can't believe I am getting heavy so quickly!
朱蒂：是。它已经瘦了。真不敢相信我胖的这么快！

Catherine: Oh, I'm sorry to hear that.
凯瑟琳：啊，听到这个我也很难受。

Judy: What can I do?
朱蒂：我该怎么办呢？

Catherine: Don't worry. Oh, right, I've got a good piece of advice about losing weight.
凯瑟琳：别急。哦，对了，关于减肥，我有一个好建议。

Judy: Have you? Great! I hope to lose 20 pounds in a month.
朱蒂：是吗？太好了！我希望一个月能减掉20磅。

Catherine: Oh, no. Crash diets are no good for you.
凯瑟琳：噢，不。急速减肥对你是没有好处的。

Judy: But I can't wait. OK, tell me what it is, please.
朱蒂：但我等不及。好了，告诉我是什么建议吧。

Catherine: Now listen, please. Cut out sugar altogether and use honey as a substitute.
凯瑟琳：好，请听清楚了。完全停止食糖，而以蜂蜜代替。

Judy: It sounds great.
朱蒂：听起来好极了。

Catherine: And you can cat as much of the following as you wish — no fat meat, fish, low fat cheese, eggs. The meat, fish and eggs mustn't be cooked with oil, butter or any fat.
凯瑟琳：你可以尽可能多地吃你喜欢的下列食物：无脂肪的肉，鱼，低脂奶酪和蛋类。烹调这些肉、鱼和蛋类时一定不要用油、黄油和其他任何脂肪类油。

Judy: Thanks a lot.
朱蒂：多谢。

Catherine: My pleasure. You'll succeed.
凯瑟琳：不客气。你会成功的。