题目：
_____________ ,they went home,________________.
A．Their work had been finished; singing and laughing
B．They had finished their work; sang and laughed
C．Their work finished; singing and laughing
D．after their work finished; singing and laughing
答案：
答案：C
题目分析：考查独立主格结构，分析句子，they went home是简单句，前面如果没有连词，就是独立主格结构，their work是逻辑主语，后面接非谓语动词，排除A，B，D项是有连词after的，所以后面的句子应该是their work had been finished;第二空使用现在分词做伴随状语，是回家的过程中同时做的事情，不是一连串并列动作。不能用sang and laughed ，选C。
点评：当分词做状语的时候，如果分词的逻辑主语与句子主语没有关系，就在分词的前面直接加上逻辑主语，形成独立主格结构，该结构在作用上久相当于一个状语从句。
