“留下来吃饭”常见的英文表达有：
Stay and have dinner （比较通用、日常的说法）
例句：Don't rush off. Stay and have dinner with us.（别急着走，留下来和我们一起吃饭。）
Stay for dinner （简洁的表达，在口语中很常用）
例句：It's getting late. Why don't you stay for dinner?（天色不早了，你留下来吃饭吧。）