hear the news,I was heart broken.为什么要变为Hearing?

问题描述:

hear the news,I was heart broken.为什么要变为Hearing?

Hearing the news,I was heart broken.
句子的 hearing 是现在分词
hearing the news
是形容词短语,修饰 I .
这是固定语法.
再举个例子:
Wagging its tail,the dog ran toward it's master.