They will have been married for 20 years by then.可以换成

They will have been married for 20 years by then.可以换成 They will have been married for 20 years by then. 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 薄冰：They will have been married for 20 years by then.到那时他们结婚将 英语翻译1.They will have been married for 20 years by then.2.I s they have been married for fifty years they said they have been married for ten years they have been married for ten years=it____________ They have been married for 15 years 同义句 They have been married for 15 years.翻译 They have been married for 20 years.为什么要用被动语态呢?