Question

帮忙分析一下这句话的主谓宾和定语从句，为什么不能省略that。

Human waste will be recovered and reused to create soil that can be used in various parts of the city.

Answer 1

Human waste 主语
will be recovered and reused 谓语
to creat soil 目的状语
that can be used 关系代词加定语，修饰先行词soil
in various parts of the city 定语从句中的地点状语。
that 可以用which 替代，但不能省，因为它是定语从句的主语。

Answer 2

Waste 主语 will be recovered and reused 谓语

追答

to create soil 不定式作目的状语
that can be used in various parts of the city 定语从句，修饰名词oil

定语从句中
that 关系代词，作主语
can be used 谓语
in various parts of the city 介词短语作状语。

由于that （关系代词）在定语从句中作主语，所以不可以省去。

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