SC Manhattan里的两个句子无法体会差别，求高手指点

我不是NN 不过说说我的理解 你参考哈
如果没有记错 曼哈顿中在讲过完时态是说 如果你要强调这个动作发生在过去的过去 用过去完成时 一般情况下是不用的
The local government built the school that was destroyed by the earthquake.
这句话我觉得只是陈述一件事情 告诉你学校在过去建的 然后在地震中毁了 并不是说建和毁没有先后 只是作者不强调
The local government had built the school that was destroyed by the earthquake.

这句话吧 作者就是想强调发生的时间顺序

我再看看曼哈顿 不过GMAT中 如果没有特殊标志 一般不用过去完成

第二句话我和你理解一样 哈

那第一句呢。。。。

The local government built the school that was destroyed by the earthquake.

The local government had built the school that was destroyed by the earthquake.

请NN详细解释这两句话 意思上的差异，自己无法体会，万分感谢~~~~！！！！！

就是强调的意思（重心）有些差异。语法上这两个句子都正确，要联系上下文的语境

第一句话，比如说某人作《政府工作报告》，或者电视台报道“过去一年十大重要事件”
The local government executed the bail-out plan, cut the local taxes, and built the school that was destroyed by the earthquake....

第二句话，强调的是，地震前后的变迁。比如电视台的专题报道“地震带给我们什么？”
某政府官员在接受记者采访时无不惋惜地表示: ...The local government had built the school that was destroyed by the earthquake.

参考了Ron的例子，
tom had been a professional football player before his leg was injured in an accident --> this sentence is meant to emphasize the abrupt ending of tom's football career, due to the accident.
tom was a professional football player before his leg was injured in an accident --> the emphasis is on the fact that tom played pro football, not on the way his career ended.

again, both correct.