外研版 Book 3 Module 4 Grammar PPT.ppt

* 不定式属于非限定动词。它除了不能做谓语外，在句中可以充当任何成分，可以作主语、表语、宾语、补语、定语和状语。 1. 作主语: 往往放在谓语动词之后, 用it作形式主语, 为了避免句子头重脚轻。 e.g. To see is to believe. It is right to give up smoking. 2. 作宾语: 作宾语时如果还带有宾语补足语, 往往把不定式放在补足语之后,而用it作形式宾语。 e.g. He wanted to go. I find it interesting to study English. 3. 做宾语补足语 e.g. He asked me to do the work with him. 在feel, hear, listen to, look at, notice, observe, see, watch, have, let, make等词后的补足语中, 不定式不带to。 不定式作宾语补足语省略to的情况有下列口诀: 一感二听三让五看半帮助。 但是这些句子如果变成被动结构时, 就必须带上to。 e.g. I often hear him sing the song. He is often heard to sing the song. 4. 作定语 e.g. I have some books for you to read. 当作定语的不定式如果是不及物动词, 或者不定式所修饰的名词或代词是不定式动作的地点, 工具等时, 不定式后面必须有相应的介词。 e.g. He is looking for a room to live in. 当作定语的不定式所修饰的名词或代词是不定式动作的承受者时, 不定式即可以用主动语态, 也可以用被动语态。但含义有所不同。 试比较: Have you anything to send? 你有什么东西要(自己)寄吗? Have you anything to be sent? 你有什么东西要(我或别人)寄吗? 5. 作状语, 表示目的, 原因, 结果或条件。 e.g. I came here to see you. We were very excited to find nobody there. He hurried to the school to find nobody there. To look at him, you would like him. 目的 原因 结果 条件 6. 作表语 e.g. My job is to help the patient. 注意: 主, 表都是不定式, 前者为条件, 后者为目的或结果。 e.g. To learn a language is to use it. 不定式的时态有：一般式、进行时、完成式和完成进行式。当不定式的逻辑主语是不定式动作的承受者时，不定式就要用被动形式。 不定式的时态和语态 1. 不定式的一般式所表示的动作通常与谓语的动作(状态)同时(或几乎同时)发生, 或是在它之后发生。 主动：e.g. I’m glad to meet you. 被动：e.g. There was nothing to be done. 2. 如果谓语表示的动作发生时, 不定式表示的动作正在进行, 这时要用进行时。 e.g. I am very glad to be working with you. 3. 如果不定式的动作发生在谓语动词之前, 就要用完成时。 主动：e.g. I’m sorry to have kept you waiting so long. 被动：e.g. The room was said to have been cleaned. 从A、B、C、D四个选项中，选出可以 填入空白处的最佳选项。 1. There were many talented actors out there just waiting ______. A. to discover? B. to be discovered??????? C. discovered???? D.