PRINCETON REVEIW 閱讀題目的問題 - 英檢

板上好像很少人用PRINCETON REVIEW
不過其實跟我問的問題也沒什麼關係
就是我做到一題閱讀的插入句


他寫說

Historians believe it had two major ancesters,of which the earlier served to
indicate wind direction. ____ Early human societies used very fragile shelters
and boats. ____Their food sources were similarly vulnerable to disruption.


插入句是

Therefore,strong winds could easily tear roofs from houses or cause
high waves that imperiled travelers.


標點符號我都是照題目打的

他給的答案是要插在第二個空格的地方
基本上文義是對
可是我發現這樣他的下句THEIR就找不到對應的人了耶
他原本應該是對應到Early human吧

請問是他題目出錯嗎


還是真正考ibt的時候不用考慮到pronoun對應的問題呢?



謝謝~

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