问题描述: 请问:有没有must have been? 1个回答 分类:英语 2014-11-11 问题解答: 我来补答 有must have been翻译为:一定(对过去事实肯定的推测)例句1.He must have been working hard these years.这些年来他一定是非常努力的. 展开全文阅读