...of the mountains that lay below 定语从句的疑惑
Though, at first, Byrd and his men were able to take a great many photographs of the mountains that lay below, 虽然开始时伯德和他的助手们拍下了飞机下面连绵群山的大量照片. 这句话的最后有个定语从句 that lay below 修饰 mountains, that 是关系代词,它指代谁,在从句中作什么语? 我不明白,位于飞机下的的群山, lay 是从句的谓语动词, below是介词吧?那飞机呢? 能帮忙从语法角度细致解释一下,这个定语从句的关系词,主语,谓语,宾语,及和主句的关系.谢谢了.