Unit 5主语从句-2025-2026学年高中英语选修一语法重难点精讲（人教版）

高中选修1人教版 【语法精讲】 主语从句专项突破 语法专版 【语法专题】主语从句专项突破 高中人教版选修1 语法精讲 语法概述：高中人教版选修1Unit5主语从句=在复合句中充当主语的从句，常由连接词that、 whether、.who、what、which、when、where、why、how等引导，在句中可置于句首或用it作形式 主语置于句首而将从句后置。 重难点讲解 重难点一：主语从句的连接词选用讲解： 1.ht引导：无实际意义，不充当成分，仅起连接作用，在句首时不可省略。 What he said is true.(错误，应用That)→That he said something is true.(正确) 2.what引导：在从句中充当主语、宾语或表语，意为”.的事物/内容”。 What we need is more time.(what作need的宾语) 3.whether引导：表示”是否'，可与or not连用，不可用if替换(if不可引导主语从句)。 Whether he will come remains unknown.（正确)→If he will come remains unknown.(错误) 4.连接代词(who/whom/whose/which)和连接副词(when/where/why/how):在从句中充当相应成 分，有具体意义。 Who will be in charge hasn't been decided.(who作主语) How we can solve the problem is a big challenge.(how作方式状语) 真题再现： 1.(2024湖北武汉期中，人教版选修1)_he will attend the meeting tomorrow is not certain, A.If B.Whether C.That D.What 答案：B解析：主语从句表示是否”含义，且位于句首，只能用whether引导。 2.(2023广东深圳月考，人教版选修1)surprised us most was his sudden decision to quit the job. A.What B.That C.Which 1 高中选修1人教版 【语法精讲】 主语从句专项突破 D.Who 答案：A解析：从句中缺少主语且表示”.的事情”，用wht引导主语从句。 重难点二：主语从句的语序讲解： 主语从句必须使用陈述语序，即”连接词+主语+谓语+其他成分”，不可用疑问语序。 错误：When will the meeting start is important.(疑问语序) 正确：When the meeting will start is important.(陈述语序) 特殊注意：即使连接词在从句中作主语，仍需保持陈述语序（此时连接词本身就是主语，后直接 接谓语)。 What caused the accident is under investigation.(what作从句主语，后直接接caused) 真题再现： l.(2024山东济南期末，人教版选修1)the team will win the championship depends on their performance in the final. A.If B.Whether C.That D.When 答案：B解析：从句需用陈述语序，且表示”是否”，whether符合要求：if不可引导主语从 句。 2.(2023 浙江杭州期中，人教版选修l)_we should take immediate action is clear to all of us. A.That B.What C.If D.How 答案：A解析：从句We should take immediate action''为完整陈述句，用hat叼引导，无实际 意义且不充当成分。 重难点三：形式主语t的用法讲解： 当主语从句较长时，为避免句子头重脚轻，常用t作形式主语，将真正的主语从句置于句末，结 构为It+谓语+主语从句”。 常见句型： 1.It+be+形容词(clear/important/.necessary.)+that从句 It is important that we should learn English well. 2.It+be+名词(fact//truth/pity.)+that从句 It is a pity that she can't attend the party. 3.It+be+过去分词(said/reported/believed..)+that从句 It is reported that a new hospital will be built here. 注意：此结构中that不可省略。 2 高中选修1人教版 【语法精讲】 主语从句专项突破 真题再现： l.(2024江苏南京月考，人教版选修1)It is necessary we should finish the project before Friday. A.what B.that C.whether D.when 答案：B 解析：it作形式主语，真正主语为从句，从句结构完整，用tht引导。 2.(2023北京海淀期末，人教版选修1)It_reported that the number of wild tigers has increased in recent years. A.is B.was C.are D.were 答案：A解析：考查'It is reported that.,句型，根据recent years可知用一般现在时，it为单 数，be动词用is 重难点四：主语从句的主谓一致讲解： 1.单个主语从句作主语时，谓语动词用单数。 What he says is not true.(从句作主语，谓语用is) 2.两个或多个并列的主语从句作主语时，若表示不同概念，谓语用复数；若表示同一概念，谓语 用单数。 What he says and what he does are different..(不同概念，用are) hat he says and does is very important.(同一概念，用is) 3.由whether..or./or连接的主语从句，谓语动词遵循”就近原则”。 Whether he comes or not doesn't matter.(靠近谓语的not视为单数，用doesn't) Whether you or he is responsible for this is not clear.(靠近谓语的he为单数，用is) 真题再现： l.(2024四川成都期中，人教版选修1)What he wants and what he needs_two different things. A.is B.are C.was D.were 答案：B,解析：两个并列的主语从句表示不同概念，谓语动词用复数，且描述客观事实用 一般现在时。 2.(2023湖南长沙月考，人教版选修1)Whether she will come or not_up to her A.is B.are C.depend 高中选修1人教版 【语法精讲】 主语从句专项突破 D.取决于 答案：A解析：whether.or not引导的主语从句视为单数，谓语用is:”取决于”不符合语 法要求，需用be动词。 易错点综合演练 1单项选择（直击重难点） 1.the new policy will be implemented remains a question. A.If B.Whether C.That D.What 2.caused the traffic accident yesterday is still under investigation A.What B.That C.Which D.Who 3.It is importantwe should protect the environment. A.what B.that C.whether D.when 4.What he says and what he does quite different. A.is B.are C.was D.were Ⅱ.用所给词的适当形式填空（强化句型结构） 1.(How)we can improve our study efficiency is worth discussing. 2.It(report)that a new bridge will be built over the river next year. 3.Whether she(come)to the party or not doesn't affect our plan. 4.What the teacher said(be)very helpful to us. Ⅲ短文填空（综合运用主语从句) 用适当的连接词填空，使短文完整通顺。 4 高中选修1人教版 【语法精讲】 主语从句专项突破 1.we will have a holiday next month is still unknown.Some students think 2.the holiday will last for a week.However,3.the school will arrange the holiday depends on the teaching plan.4.can get the first prize in the exam is not important.The most important thing is 5.we have tried our best. V.连词成句（聚焦句型结构） 1.that,important,it,is,we,English,learn,well,(. 2.what,he,said,surprised,us,most,( 3.whether,he,will,come,tomorrow,not,or,certain,is,(. 4.how,solve,we,problem,the,need,to,discuss,( V.按要求改写句子（巩固否定、疑问句式） l.That he will attend the meeting is true..(改为否定句) 2.What he did was right..(改为一般疑问句并作否定回答) 3.It is clear that she is good at English.(对划线部分提问) 4.Whether they will go there depends on the weather.(改为同义句) 综合演练参考答案 I.单项选择：1B2.A3B4.B Ⅱ.用所给词的适当形式填空：1.How2.is reported3.will come4.is Ⅱ.短文填空：1.Whether2.that3.how4.Who5.that 高中选修1人教版 【语法精讲】 主语从句专项突破 V.连词成句： 1.It is important that we learn English well. 2.What he said surprised us most. 3.Whether he will come tomorrow or not is certain 4.How we solve the problem needs to be discussed. V按要求改写句子： 1.That he will not attend the meeting is true. 2.Was what he did right?No,it wasn't. 3.What is clear? 4.It depends on the weather whether they will go there. 6