Once having made a promise,you should keep it.

分类: 作业答案 • 2021-12-20 08:29:50

问题描述：

Once having made a promise,you should keep it.
have为什么要用having?

答

having 是非谓语形式,表示主动,逻辑主语是you.you是主动地make promise的
“一旦已经做出承诺,你就应该信守承诺”不是有once开头吗？怎么还用having?once只是个连词，不影响非谓语动词的使用。