Question

to have been done用法

Answer 1

to have been done 不定式的完成式的被动形式用法:
不定式的完成被动式表示发生在谓语动作之前的被动动作。

扩展资料

　　It was hard to visualize how it could have been done.

　　很难想象这是如何办到的。

　　The two were said to have been on first-name terms.

　　据说这两人关系很熟。