介詞短語(yǔ) in the world 和定語(yǔ)從句 who are smarter than her都是修飾賓語(yǔ)從句中的主語(yǔ) many people 的.由于, 介詞短語(yǔ)較短, 為了保持句子平衡,最好把介詞短語(yǔ)置于定語(yǔ)從句和先行詞之間.這類不緊靠先行詞的定語(yǔ)從句語(yǔ)法上叫【分隔定語(yǔ)從句】

再如：
This is the only book on the shelf that you can borrow.
He is the only student in my class who has failed in the exam.

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