文章授權：貝塔語言出版

So Robert received an email during the first days of December. In the email the teacher said they were not available for a project 24/7. Robert looked at this for a while, wondering what it meant. The teacher was writing about future projects, but the date was in the past. Robert looked back in his dairy to the July days of last summer, but there was nothing to show that a meeting had taken place on 24 July. He called his colleague-Richael, “Hey did we have a meeting with these guys on July 24?” “No, not that I remember,” said Richael. “Do we have anything planned for 27 July next year?” “Are you kidding, we are not even at the end of this year yet!” Robert was still puzzled. Then he asked his English friend if he knew what it meant. “Oh yeah, it’s an idiom. It means 24 hours a day, 7 days a week. Basically it means ‘all the time’. I’m not available 24/7 means I’m not available all the time.” 

羅伯特在 12 月初收到一封 email。Email 中老師提到我們這個專案時間不允許 24/7。羅伯特看到這時楞了一下，心想這是什麼意思，老師是在說未來規劃的安排日期，可怎麼時間是七月呢？羅伯特看了一下今年夏天七月份行事曆，但是記事本上 7 月 24 日並沒有任何會議的安排。他打給了同事瑞秋「我們 7 月 24 日有跟這些傢伙開會嗎？」「我記得沒有耶！」瑞秋回應。「那我們明年的 7 月 24 日跟老師有任何計畫嗎？」「你在開玩笑嗎？我們今年都還沒有過完！」羅伯特仍然一頭霧水。然後羅伯特問了一位英國朋友是否知道 

24/7 (twenty-four-seven) 是什麼意思？
唉呀！這是一個慣用語。
一天有 24 小時，一週有 7 天。

基本上是說無時無刻全年無休的意思。
I’m not available 24/7. 
則是指「我不是都有空。」