Question

求英语大神分析一下这段话的语法

First,the War of Resistance against Japan disrupted Japanese army's "northward advance"plan.Before WWII ，Japanese strategists disputed among themselves over the direction of Japanese military invasion,i.e. "advancing southward" or "advancing northward."Northward advance" would mean war with the Soviet Union, to be fought mainly in the land battles.However,as a million-strong Japanese land forces had been bogged down deep in the Chinese battlefield,Japan simply did not have enough army troops to launch military attacks against the Soviet Union.前半段都是一般过去时为什么However,as a million-strong Japanese land forces had been bogged down这句用过去完成时？求解大神，在线等！

Answer 1

没看原文全靠猜 as可以表原因 如果是Japanese land forces had been bogged down之前已经发生就可以用过去完成时

追问

首先，中国抗战破坏了日军“北进”计划。二战前，日本战略界在其侵略方向上有“南进”“北进”之争。“北进”是指对苏作战。以陆战为主，但日本百万陆军深陷中国战场，已无力对苏作战。 附译文

追答

你还不是要我看原文。。
这篇东西是讲二战时的，不是之前。
二战用过去式 二战时一百万日军兵力已经深陷中国战场 用过去完成时 然后是讲深陷中国战场之后的策略 恢复普通过去式

追问

Before WWII ，Japanese strategists disputed among themselves over the direction of Japanese military invasion这句也是讲二战前为什么不用完成时呢

追答

这在陈述一个一般事实。一般式就可以