今天是放假第一天用英语怎么说

"Today is the first day of vacation" 是今天是放假第一天的英文表达。

这个短语是由两部分组成的："today"表示今天，"is the first day of vacation"表示放假第一天。

例句：

"Today is the first day of vacation, I'm so excited!"
(今天是放假第一天，我太兴奋了！)
"I can't believe it's finally here, today is the first day of vacation."
(我简直不敢相信终于到了，今天是放假第一天。)
"Today is the first day of vacation and I plan to relax and enjoy it."
(今天是放假第一天，我打算放松和享受它。)