为何before,after表一点,ago,later表一段?
问题描述：
为何before,after表一点,ago,later表一段?
答
举例说明
1 He hadn't known the news before yesterday
2. He came back after 10 o'clock
3. He left home three years ago
4. He came back three days later
答
1.before he arrived here,after he arrived here在这两个句子中,在他到达这里之前/后,是一个无限长的时间段,那么这个时间段的终结点----->到达的一瞬间,作为一个里程碑,谈论起来才会有意义吧?故before,after后面的...