非谓语动词中,ing形式分两种,一是动名词,二是现在分词
Hearing the news ,he jumped with joy（现在分词的一般式作时间状语）
Having finished his homework ,the boy went out to play（现在分词的完成时作时间状语)
He sat there,reading a book(在分词的一般式作伴随状语）