Not having met( not met ) him for a long time,I can not tell you what he is like.请问为什么要填Not having met?而不是Don’t meeting?

问题描述:

Not having met( not met ) him for a long time,I can not tell you what he is like.
请问为什么要填Not having met?而不是Don’t meeting?

have 现在完成 do 一般现在

  Not having met完整的语法名称叫“现在分词的主动完成式”,为非谓语动词的一种,既然不是谓语动词,就不能用否定谓语动词的方式来否定非谓语动词;另外,助动词do后总是用动词原形。

这是现在分词的否定式【Not +v-ing】,作状语表原因
由于很久没见到他了,所以没法同你讲清楚他长得怎么样了.
由于分词having met 是先于谓语can't tell 发生的,故用现在分词的完成式
等于:
【Because I haven't met him for a long time】,I can not tell you what he is like.

这是个语法嘛,就是这样的,只可意会,不可言传