她在学校吃午饭用英语怎么说

"She is having lunch at school" 是她在学校吃午饭的英文表达方式。

"Having lunch" 是 "吃午饭" 的意思，来源于英语动词 "have" 和名词 "lunch" 的结合。"Have" 是一个动词，有 "拥有"、"吃"、"喝" 等多种意思；"Lunch" 是一个名词，表示 "午饭"。

以下是一些带有 "having lunch" 的英文例句及其中文翻译：

I'm having lunch with my friends at the park. (我正在公园和我的朋友们一起吃午饭。)
She's having lunch at the office today. (今天她在办公室吃午饭。)
They're having lunch together every day. (他们每天一起吃午饭。)