英语句子结构问题He has been able to tell us more about the active volcanoes than any man alive.

分类: 作业答案 • 2022-01-09 18:01:45

问题描述：

英语句子结构问题He has been able to tell us more about the active volcanoes than any man alive.
知道were able to 意思.为什么是has been ,

答

has been able to 是be able to 的现在完成时形式