必修三 unit4 主语从句.pptVIP

The Subject Clause主语从句;一、主语从句的定义 二、主语从句的构成 三、主语从句的引导词 四、 it 可作形式主语 五、主语从句需注意的问题 ;;一、主语从句的定义： 在复合句中位于谓语动词或系动词之前充当主语的句子，叫主语从句。 That he is still alive is a wonder. 二、主语从句的构成： ;三、主语从句的引导词： 从属连词: that, whether； 连接代词: who , whom, whose, which, what ； whatever，whoever，whichever 连接副词: when, where, how, why。 ; that that引导主语从句, that在从句中只起连接作用， 不作成分，没有意义，不能省略。 That he will come is certain. 2. whether 1) whether引导主语从句，译为“是否”, 不能省略。 if 不能引导表语从句。 Whether?he’ll?come?here?is a problem.; ;When he will be back depends on the weather. Where the test will be given is not yet decided. Where and when he was born is a secret. Why he came here is not known. How we can protect the endangered animals needs to be discussed. How many people died in the earthquake was unknown.;注意：whatever，whoever，whichever在主语从句中不含疑问意义。它引导主语从句，并在从句中作主语、宾语或表语等。;四、it 可作形式主语 为了使句子保持平衡，避免头重脚轻,经常用 it 作形式主语,主语从句放在后面作真正的主语. 其结构为： It + 谓语动词/系动词 + 宾语/表语 + 主语从句. 例如: That we shall be late is certain. = It is certain that we shall be late. 1. That the earth is round is known to all. = It is known to all that the earth is round. 2. whether they would support us was a problem . = It was a problem whether they would support us. ;1.? It + be + 形容词 + that 从句(obvious,?true,?surprising,?good,?wonderful,?funny,?possible,?likely,?certain,?…) 如： It?is?certain?that?she?will?do?well?in?her?exam.? ? 2. It + be + 名词词组 + that 从句 (an?honor,?a?fact,?a?pity,?…）如： It’s?a?pity?that?we?can’t?go.??;3.????????It + be + 过去分词 + that 从句 (said,?reported,?believed,suggested,known,thought,?expected,?decided,???…） 如： It?is?said?that?Mr.?Green?has?arrived?in?Beijing.? =Mr.Green is said to have arrived in Beijing. 主语+is said ;He is said to go abroad soon.据说他不久要出国。 表示不定式所表示的动作尚未发生或将要发生 The tigers are said to be endangered.据说这些虎处于濒危状态 表示一般情况(尤其是当不定式表示状态而非动作时)。 They are said to