For most people the sea was remote, and with the exception of early intercontinental travellers or others who earned a living from the sea, there was little reason to ask many questions about it, let alone to ask what lay beneath the surface.
【译文】除了早期漂洋过海的旅行者或靠海谋生的人之外，对大多数人来说，大海是遥远的，没有必要提出太多问题，更别说思考大海海底的东西了。
【析句】复合句，本句主干为the sea was remote and there was little reason to…，and连接两个并列句子，两个句子之间又有with the exception of…作伴随状语，伴随状语中又包含who earned a living from the sea定语从句修饰others.最后是习惯let alone…，注意let alone后的动词形式与前面主句动词形式相同。