1、not worth a red cent

Worthless.

一文不值

e.g. I don't know how I'm going to tell that woman that her prized collectibles are not worth a red cent.

我不知道我要怎么告訴那位女士，她珍貴的收藏品其實一文不值。

a red cent

a cent is the smallest coin in value in American money and is worth very little.

在美國的貨幣里面值最小的硬幣，幾乎不值錢。

2、a red eye

an overnight airplane flight. a flight that leaves late at night and arrives early the next morning

夜間航班。深夜起飛，第二天清晨到達的航班。(American informal)

e.g. We took the red eye from Seattle to NewYork.

我們從西雅圖乘深夜航班去紐約。

3、a red-letter day

a day that is very important or very special

非常重要或特別的一天

e.g. The day our daughter was born was a real red-letter day for us.

我們女兒出生的那一天對我們來說真的是非常特別的一天。

4、(boy,) is my face red!

An exclamation of acute embarrassment or mortification.

出于極度尷尬或屈辱的驚叫。（這里的“boy”也是感嘆詞啦(˶‾᷄ꈊ‾᷅˵ )！沒有實際意義哦！）

e.g. I can't believe I was calling my client by the wrong name. Boy, is my face red!

我不敢相信我竟然叫錯了客戶的名字。真是太難堪了！

e.g. I spent so long on that report, only for it to be laughed at by everyone in class. Is my face red!

我在那篇報告上花了那么長的時間，也只是被班上每個人嘲笑。真是太丟臉了！

5、red as a cherry

bright red.

亮紅；緋紅

同樣用法的還有：red as a poppy; red as a rose; red as a ruby; red as blood

e.g. When she came in from ice-skating, Clara's nose was as red as a cherry.

當Clara滑完冰回來，她的鼻子紅彤彤的（像櫻桃一樣紅）。

e.g. When her boss praised her in front of the whole office, Emily turned red as a poppy.

當Emily的老板在整個辦公室前贊賞她，她臉一下子就紅了。

6、red tape

official rules which do not seem necessary and make things happen very slowly

看起來不必要且導致拖延的官樣規則和程序。“繁文縟節”

e.g. My passport application has been held up by red tape.

我的護照申請被繁文縟節擱置了。

e.g. Because of red tape, Frank took weeks to get a visa.

由于繁文縟節，Frank花了好幾周才拿到簽證。

e.g. Red tape prevented Jack's wife from joining him abroad.

繁文縟節導致Jack的妻子不能和他一起出國了。

7、see red

to be very angry.

非常生氣。

e.g. Bill really saw red when the tax bill arrived.

當稅單送到，Bill真的憤怒了。

e.g. Some Internet customers are seeing red as a result of the new virus that slowed Web traffic last week.

上周一種新的病毒減拖慢了網絡流量，一些網絡用戶對這個結果十分生氣。

e.g. When he laughed in my face, I just saw red.

他嘲笑我的臉時，我非常生氣。

8、red sky at night, shepherd’s delight

A red sky at sunset is a sign that good weather will follow. The full phrase is "Red sky at night, shepherd's delight; red sky in the morning, shepherd's warning.”

日落時的紅色天空，是下一天好天氣的征兆。完整的說法是“傍晚天紅，牧羊人高興；早晨天紅，牧羊人當心。”——這是一條關于天氣的諺語，人們借助這些朗朗上口的諺語來判斷明天的天氣，其實也就是我們常說的“朝霞雨，晚霞晴” (ૢ･ω･ᴗ)。

e.g. I think we're going to have a nice sunny day tomorrow. Look at that sunset—red sky at night, shepherd's delight.

我想明天將會是一個美好的晴天。你看那個日落——晚霞晴。

9、red ink

debt; indebtedness as shown in red ink>債務；債務在財務報表中用紅色墨水表示。

e.g. There is too much red ink in my financial statement.

我的財務報表里太多赤字了。

e.g. Too much red ink and the company will collapse.

這個公司太多的赤字，就要倒閉了。

和它相對的是：out of the red

out of debt; into profitability.

擺脫債務；有盈利能力。

e.g. This year our company is likely to get out of the red before fall.

今年我們的公司在秋季之前可能就擺脫赤字了。

e.g. If we can cutdown on expenses, we can get out of the red fairly soon.

如果我們可以削減開銷，我們很快就能拜托債務了。

10、paint the town red

to go out and enjoy yourself in the evening, often drinking a lot of alcohol and dancing

晚上出去玩得開心，經常是喝很多酒，還跳舞。(informal)

e.g. Jack finished his exams today so he's gone out to paint the town red.

今天Jack考完試了，所以他出去狂歡作樂了。

e.g. They were out painting the town red last night.

他們昨晚出去嗨了。

（來源：滬江英語）