在学校请假的英语表达方式可以是："request a leave of absence from school" 或者 "ask for a leave of absence from school"。

"Leave of absence" 是一个固定短语，意思是"请假"或"休假"。它的来源可能源自于军队术语，在军队中，"leave of absence" 指的是允许军人离开基地的休假。随着时间的推移，这个术语也被广泛用于其他领域，包括学校。

下面是一些使用 "request a leave of absence from school" 或 "ask for a leave of absence from school" 的英文例句，以及它们的中文翻译：

"I need to request a leave of absence from school for personal reasons." (我需要因个人原因请假。)
"I'm writing to ask for a leave of absence from school for the next two weeks due to a family emergency." (我写信是为了请求下两周的假，因为有家庭紧急事件。)
"Can I request a leave of absence from school for a few days to attend a funeral?" (我可以请几天假去参加葬礼吗？)
"I'd pke to request a leave of absence from school for the month of June to go on a mission trip." (我想请6月份的假去参加传教之旅。)