同学你好，该知识点来自沪江网校《英语零基础直达大学六级【超值特惠班】》的课程，想要更系统的学习，欢迎进入课程学习。不仅可以和更多的同学一起学习，而且还有老师、助教随时的学习指导和知识点解答哦。

同学你好~
after 在……之后
after it had begun 在动工之后
My sister left after it had begun. 在动工之后，我姐姐离开。
这样和前一句就是一个意思了。

再看几个after的例句
We'll leave after lunch.
我们将在午饭后动身。

After winning the prize she became famous overnight.
她获奖后一夜之间成名了。

I'll call you after I've spoken to them.
我和他们谈了以后就给你打电话。

祝同学学习进步~