2023年初中英语语法学习之主语从句用法归纳

2023年初中英语语法学习之主语从句用法归纳主语从句是在句子中充当主语的从句。　它与其它名词性从句一样，通常由连接代词或连接副词引导。主语从句在复合句中作主句的主语,引导主语从句的词有从属连词that, whether以及连接代词who, what, which, whoever, whatever, whichever和连接副词when, where, why, how等.例如:That she was chosen made us very happy.她当选了使我们很高兴.What caused the accident is a complete mystery.是什么导致了这次事故还完全是一个谜.Whether she will come or not is still a question.她是否来还是一个问题.Which team will win the match is still unknown.哪个队会赢得这场比赛还不知道.Whoever comes to the party will receive a present.参加聚会的每一个人都将收到一份礼物.When they will start has not been decided yet.他们何时出发还没决定. 注意:上述例句中的主语从句都是放在句首,但有时为了使句子结构平衡,避免"头重脚轻",常用it作形式主语,而把从句放在后面.例如:It is a pity that she has made such a mistake.她犯了这样一个错误,真是遗憾.It depends on the climate whether they are going shopping today.他们是否今天去购物还得看天气情况.1. 由that 引导的主语从句 That she lacks experience is obvious. 她缺少经验，这是显然的。 That you will win the medal seems unlikely. 你想获得奖牌看起来是不可能的。 That you are so indifferent bothers me. 你如此冷淡使我很烦恼。2. 由连接代词引导的主语从句 What you need is more practice. 你需要的是更多的练习。 Which of them escaped from the prison is still a mystery. 他们哪一个是从监狱里逃跑的，仍然是个谜。3. 由连接副词引导的主语从句 When they will come hasn't been made public. 他们什么时候来还没有公布。 Where she has gone is not known yet. 她去了哪儿，还不知道。 How the prisoner escaped is a mystery. 犯人是如何逃跑的是个迷。 Why he did it will remain a puzzle for ever. 为什么他做那件事将永远是个谜团。4. 由whether引导的主语从句 Whether he will join us won't make too much difference. 他是否加入我们，没有太大的差别。 Whether she is coming or not doesn't matter too much. 她来不来都无关紧要。5. 由 what 引导的主语从句 What she did is not yet known. 她干了什么尚不清楚。 What I want to know is this. 我想知道的就是这事。 What you need is more practice. 你所需要的是更多的训练。6. 以it作形式主语的主语从句1） it + be + 形容词 + 从句 It is doubtful whether she will be able to come. 她是否能来令人怀疑。 It is essential that he should be here by the weekend. 周末之前，他应该到这里是必要的。 It was clear (that) his words pleased her. 显然他的话使她很高兴。2） it + be + 名词 + 从句 It is common knowledge that the whale is not a fish. 鲸鱼不是鱼，这是常识。 It is no surprise that Bob should have won the game. 鲍勃会赢得这场比赛，这不足为奇。3） it + 动词 (+宾语或状语) + 从句 It does not interest me whether you go or not. 我对你去不去不感兴趣。 It shocked me that Peter did not tell anybody where he was. 让我吃惊的是彼得没有告诉任何人他在哪里。 It happened that she was out. 碰巧她外出了。4） it + 动词的被动语态 + 从句 It is thought that he is the best player. 大家都认为他是最好的选手。 It is estimated that the vase is 2000 years old. 据估计这个花瓶有2000年的历史。7. 由whatever, whoever, whichever 等引导的主语从句 Whatever was said has left us much to think. 这里说的话都应当保密。 Whoever says that is a liar. 说那话的人是个骗子. Whichever comes in first will receive a prize. 谁先到就会获奖。8. 由 just because 引导的主语从句由just because 引导的主语从句通常只用于 "Just because...doesn't mean..."句型中。 Just because her eyes don't tear, doesn't mean her heart doesn't cry. 只是因为眼泪没有掉下来，并不代表她在心里没有哭泣。 Just because he's over sixty doesn't mean he must retire. 仅仅是年过60这一点并不意味着他一定退休。 构成主语从句的方式有下列两种：（1）关联词或从属连词位于句首的从句+主句谓语+其他成分。它们一般是译在句首，作为主从复合句的主语。这样的词有关联词what，which，how，why，where，who，whatever，whoever，whenever，wherever及从属连词that，whether，if.如：例题1：What he told me was only half-truth.分析：其中关联词可译“…的”，放在后面。参考译文：他告诉我的只是些半真半假的东西而已。例题2：Whether an organism is a plant or an animal sometimes taxes the brain of a biologist.分析：whether可以译成“是否，是…还是”，然后适当安排位置。参考译文：一种生物究竟是植物还是动物，有时使生物学家颇伤脑筋。（2）it+谓语+that（whether）引导的从句。如果先译主句，可以顺译为无人称句。有时也可先译从句，再译主句。如果先译从句，便可以在主句前加译这。如：例题3：It can be seen that precleaning alone would not reduce the total sulfur content of the four coals to levels anywhere near the standards.分析：这样的句子可以译成无人称句，常用来表示事实，常理等。参考译文：可以看出，这四种煤的总含硫量仅靠预先洗选将不能降低到完全接近标准规定的水平。例题4：It is a matter of common experience that bodies are lighter in water than they are in air.分析：有时为了使译文成分完整，可以补充上泛指的主语（如人们…、大家…）。类似的结构还有：it is（universally）known that…大家都知道…it is believed that…人们都相信…。参考译文：物体在水中比在空气中轻，这是一种大家共有的经验。