he sat that there,--------(read) a book 答案是reading,是为什么

Question

he sat that there,--------(read) a book 答案是reading,是为什么

Answer 1

现在分词做伴随状语
　　伴随状语的特点是：它所表达的动作或状态是伴随着句子谓语动词的动作而发生或存在的.例如：
　　①He sat in the armchair,reading a newspaper.
　　他坐在扶手椅里读报.
　　②All night long he lay awake,thinking of the problem.
　　他整夜躺在床上睡不着,思考着那个问题.