语法书告诉你动名词的完成体形式having done表示动名词的动作先于谓语动作已经发生并结束。 但非正式语体通常用doing 代替having done。 after doing 和 after …
High quality example sentences with “after having assured” in context from reliable …
假使说“某个时刻（point of time）或日期或事件以后”，尽可用after。 例如：He will (或would) arrive after four o'clock (或after 5 July， …
1. after 和before 用作连词时，不可省略主语和be 动词；而when 和while 就可以省略。 2. 本句为 …
they are essentially the same, both being a different form of 'confirm'. 'After having …
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