他们吃过了晚餐英文怎么说

他们吃过了晚餐可以用英文表示为 "They have had dinner." 或者 "They have eaten dinner."

这个表达方式源于英语中动词 "have" 的过去完成时态的用法。在英语中，过去完成时态表示在过去的某个时间之前已经完成的动作或状态。

下面是一些使用过去完成时态的英文例句及其中文翻译：

She had finished the project before the deadpne. (她在截止日期之前完成了这个项目。)
He had eaten breakfast before he left for work. (他在上班前已经吃过早餐了。)
They had already booked their tickets before we invited them to join us. (在我们邀请他们加入我们之前，他们已经订好了机票。)