提这种问题的学生在私塾里都是要挨板子的。这是 短文Hope and Dashed Hope 中的一句话，你把完整句子中的一部分拿来分析句子结构，本不是主语的名词被误认为是主语，你永远也不会有正确答案的。记住：提问题一定要给出完整的句子，不要自以为是地随意截取其中一部分。

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One spring I planted corn too early in a bottom land so flood-prone that neighbors laughed. I felt chagrined at the wasted effort. Summer turned brutal---the worst heat wave and drought in my lifetime. The air-conditioned died; the well went dry; the marriage ended; the job lost; the money gone. I was living lyrics from a country tune---music I loathed. Only a surging Kansas City Royals team buoyed my spirits.

Looking back on that horrible summer, I soon understood that all succeeding good things merely offset the bad. Worse than normal wouldn’t last long. I am owed and savor the halcyon times. The reinvigorate me for the next nasty surprise and offer assurance that can thrive. The 50-percent theory even helps me see hope beyond my Royals’ recent slump, a field of struggling rookies sown so that some year soon we can reap an October harvest.

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上一段说作者种玉米失败了，婚姻破裂，丢了工作，钱也花光了。唯独堪萨斯城市皇家棒球队执教让他有了一些希望。你的句子就是下面这一段的最后一句话。你提问的a field of struggling rookies sown so that some year soon we can reap an October harvest这部分并不是一个句子，而是hope的同位语，是一个名词词组。作者执教的棒球队员处于低潮，队员都是新手，作者把这些新队员比作他种到地里的玉米，以便在十月的棒球赛中能取得好成绩，但他用十月收获的好收成来比喻比赛取得好成绩。在这个名词词组中，a field of struggling rookies为中心词，sown so that some year soon we can reap an October harvest.为过去分词短语作定语，so that从句是sown的目的状语。