第09讲-长难句讲义名词性从句（一）-2027年高三英语一轮复习专项

③ 第二层（主从定位）：
形式主语：It
主句主干：It’s estimated...
真正主语（主语从句，that引导）：that the global demand for electricity could more than double by 2050
that 在从句中不作任何成分，只起连接作用

④ 第三层（修饰剥离）：
for electricity → 介词短语作定语，修饰 demand
more than → 程度副词短语，修饰 double
by 2050 → 介词短语作时间状语

⑤ 第四层（最小单元）：
形式主语结构：It is estimated that...
主语从句主干：demand could double.

树状结构图：

[It] [is estimated] [that the global demand for electricity could more than double by 2050]

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形式主语真正主语（that 引导的主语从句，that 不作成分）

⚠️ 核心考点：
It 作形式主语，that 从句后置
that 在主语从句中不作任何成分，不可用 what 替换（从句结构完整）

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⭐ 例2（2024浙江1月卷·语法填空）难度：★★★☆☆

If most of their customers are happy to buy larger quantities, that’s what they’ll promote.

① 全句观：
连词数：2个（If, what）｜谓语动词数：3个（are, 's, 'll promote）｜非谓语动词：1个（to buy）
结构类型：what 引导的表语从句，嵌套在 if 条件状语从句之后

② 第一层（并列切分）：
无并列连词

③ 第二层（主从定位）：
条件状语从句（If引导）：If most of their customers are happy to buy larger quantities
主句主干：that’s...
表语从句（what引导）：what they’ll promote → 位于 is 之后
从句缺少宾语（promote 的宾语），指物，用 what，意为“……的东西”

④ 第三层（修饰剥离）：
to buy larger quantities → 不定式作状语（修饰形容词 happy，表原因，相当于“因购买更大包装而高兴”）
that → 指示代词，指代前面整件事

⑤ 第四层（最小单元）：
条件状语从句：their customers are happy.
主句：that’s...
表语从句：what they’ll promote.

树状结构图：

[If most of their customers are happy to buy larger quantities] [条件状语从句]

[that] [is] [what they’ll promote]

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主语系动词表语从句（what 作 promote 的宾语）

⚠️ 核心考点：
what 在表语从句中作宾语，与例1（that 不作成分）形成对比
表语从句位于系动词之后，解释主语（that）的内容

⭐ 例3（2025新课标I卷·阅读C篇）难度：★★★★☆

Although these campaigns were widespread, the reality is that the majority of the western cities were completely redesigned around the needs of the motor car.

① 全句观：
连词数：2个（Although, that）｜谓语动词数：3个（were, is, were redesigned）｜非谓语动词：0个
结构类型：Although 让步状语从句 + that 引导的表语从句

② 第一层（并列切分）：
无并列连词

③ 第二层（主从定位）：
让步状语从句（Although引导）：Although these campaigns were widespread
主句主干：the reality is...
表语从句（that引导）：that the majority of the western cities were completely redesigned around the needs of the motor car
表语从句结构完整（the majority...were redesigned），不缺成分，用 that（不作成分，只

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起连接作用）

④ 第三层（修饰剥离）：
of the western cities → 介词短语作定语，修饰 majority
completely → 副词，修饰 redesigned
around the needs of the motor car → 介词短语作状语

⑤ 第四层（最小单元）：
让步状语从句：campaigns were widespread.
主句：reality is...
表语从句：cities were redesigned.

树状结构图：

[Although these campaigns were widespread] [让步状语从句]

[the reality] [is] [that the majority of the western cities were completely redesigned...]

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主语系动词表语从句（that 不作成分）

⚠️ 核心考点：
that 引导表语从句时，从句结构完整，that 不作任何成分
与例2（what 作宾语）形成对比：what 作成分，that 不作成分

⭐ 例4（2024新课标I卷·读后续写）难度：★★★★★

What further astonished and touched me was that he handed me some cash for taking a bus.

① 全句观：
连词数：2个（What, that）｜谓语动词数：4个（astonished, touched, was, handed）｜非谓语动词：1个（taking）
结构类型：what 引导的主语从句 + that 引导的表语从句，一句中同时出现两种名词性从句

② 第一层（并列切分）：
and 连接两个并列谓语：astonished / touched

③ 第二层（主从定位）：
主语从句（What引导）：What further astonished and touched me → 作 was 的主语
主句主干：What astonished and touched me was that...
表语从句（that引导）：that he handed me some cash for taking a bus → 位于 was 之后
主语从句缺少主语（astonished 的主语），用 what
表语从句结构完整（he handed me some cash），用 that（不作成分，只起连接作用）

④ 第三层（修饰剥离）：
for taking a bus → 介词短语作目的状语
some cash → handed 的直接宾语，me 为间接宾语

⑤ 第四层（最小单元）：
主语从句：What astonished and touched me.
主句：...was that...
表语从句：he handed me some cash.

树状结构图：

[What further astonished and touched me] [主语从句，what 作主语]

[was] [that he handed me some cash for taking a bus]

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系动词表语从句（that 不作成分）

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