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Unit 3 Back to the past Grammar and usage Predicative clauses 表语从句 1. 定义:在句子中充当表语的从句 系动词(连系动词) 分类 例词 1、Be系动词 am, is, are, was, were 2、感官系动词 smell, taste, feel, sound 3、表象系动词 look,seem,appear 4、变化系动词 become, grow, turn, fall 5、持续系动词 Keep,continue,remain,stay 6、终止系动词(结果) prove,turn out 基本句子结构:主+系+表 2. 由连接词that, whether 引导的表语从句 that 在引导表语从句时无词义;而whether有词义,意为“是否”。这时主句的主语常常是抽象名词,如problem, result, chance, suggestion, question, reason 等,表语从句对主句主语进行说明,解释等。 The result of the invention of steam engines was that human power was replaced by mechanical power. 发明蒸汽机的结果是机械力取代了人力。 The main question is whether you want your arms inside or outside the sleeping bag. 主要的问题是你想要你的手臂在睡袋的里面还是外面。 特别注意:if 也有“是否”的含义,但连接表语从句不可以用if, 而要用whether. The question is whether we will hold our sports meet next week. 3. 由连接代词what, which, who, whom, whose, whatever, whichever, whoever, whomever等引导的表语从句。 As John Lennon once said, life is what happens to you while you are busy making other plans .正如约翰.列侬曾经说的,生活就是当你忙于制定其他计划时发生在你身上的事情。 The problem was who could do the work. 问题是谁能做这项工作。 4. 由连接副词when, where, how, why 等引导的表语从句 The problem is when we can get a pay rise. 问题是我们什么时候可以获得加薪。 5. 由连词 because, as if/as though 等引导的表语从句 as if 犹如,好像,好似,仿佛 as though 仿佛;好像 From space, the Earth looks blue. This is because about 71% of its surface is covered by water. 从太空看,地球是蓝色的。这是因为地球表面大约71%的面积都被水覆盖。 It's as if the brain is preserving the most important memories. 就好像大脑在保存它最重要的记忆。 特别注意:as if/ as though 引导的表语从句常置于连系动词look, seem, sound, be ,become等后面。从句陈述的内容如果有明显根据,很可能发生, 就用陈述句语气;如果与事实不符,就用虚拟语气(主句是一般现在时,从句就用一般过去时, be 一般用 were; 主句是一般过去时, 从句用过去完成时)。 Dark clouds are gathering. It looks as if it's going to rain. 乌云正在聚集。看起来好像要下雨了。(有明显根据) I feel as if I were at home while here. 在这儿我感觉像在自己家一样。(与事实不符) Applying the rules B 1 Complete the sentences with proper linking words to form predicative clauses. Applying the rules 1. I got six books from the library. The question is _ one I should read first! 2. The truth is _ there are many rea