Question

That's the house where she once lived.=That's the house （　　）she　once　lived．

为什么

Answer 1

That's the house where she once lived.
答：=That's the house （in which）she once lived．

解析：原句是用关系副词引导的定语从句，修饰名词house，改写后的句子是用介词和关系代词引导的定语从句，修饰名词house，两句句意完全一致。

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