They have been married for 20 years.为什么要用被动语态呢?

They have been married for 20 years.为什么要用被动语态呢? They have been married for 5 years.这个句子为什么要用被动语态.还要5年前面为什么用介 1.They have been married for three years.是完成时的被动语态吗? 他们结婚十年了 They have been married for ten years 为什么要用have been they have been married for fifty years They will have been married for 20 years by then. we've been married for many years 为什么用been married啊?是表达完成式被动 he has been married for three years 句中has been married 是被动语态 they said they have been married for ten years have been married 是被动语态吗 英语?They will have been married for 20 years by then.请问been在句 They will have been married for 20 years by then.这里的been 表示什