unit 3 the world online grammar and writing学案

　　 助动词

　　[语法初识]

原句感知 自主探究 ①I am speaking in favour of the Internet.

②There are two main points which must be included when we analyse the Internet.

③With the touch of a button or the click of a mouse, a student will find abundant information.

④These problems do not occur as often when people use traditional reference materials.

⑤To help solve this problem, a special clinic was opened in Beijing in 2005.

⑥One university did a study about the students who had dropped out. (1)按英语词类划分，以上各句中黑体部分的词均为助动词。

(2)以上各句中黑体部分的词均无词汇意义，不能单独作谓语。

(3)②⑤句中黑体部分的词在句中与实义动词一起构成被动语态。

(4)①③⑥句中黑体部分的词在句中与实义动词一起构成时态。

(5)④句中黑体部分的词在句中与实义动词occur一起构成否定。 　　[语法剖析]

语法点一 助动词的概念 　　　　协助主要动词构成谓语动词词组的词叫助动词。被协助的动词称作主要动词(Main Verb)。助动词是语法功能词，自身没有词义，不可单独使用，它没有对应的汉语翻译，用于构成时态、语态。

语法点二 助动词的分类 　　

类别 例词 特点 基本助

动词 be, do, have 无词汇意义，只有语法作用，协助主要动词构成时态、语态、否定句、疑问句等