讲解By correlating markings made in various parts of the world,historians have been able to r
问题描述：
讲解By correlating markings made in various parts of the world,historians have been able to r
前半句 ing做什么成分?
答
前半句不是个完整的句子啊,by 引导的状语提前了,原句的意思是--“通过比较在世界各地做的标记（marking）,历史学家终于能够.”“markings made in various parts of the world”做correlate的宾语,marking是做名词,m...