Unit 1 Life Choices Grammar——动词不定式的用法 课件-2022届高三英语一轮复习北师大版（2019）必修第一册

Part Ⅲ　语法专题 ——动词不定式的用法 动词不定式在句中可作主语、宾语、定语、表语、状语和宾语补足语。 观察与发现 1．动词不定式作主语 [观察1] To know oneself is difficult.人贵有自知之明。 To say is one thing and to do is another.说是一回事，做又是另一回事。 [发现1]不定式具有名词的特征，可在句子中充当主语。 [观察2] It's rude to turn your back to your teacher and refuse to answer. 背对着老师、拒绝回答问题是不礼貌的。 It seemed a pity to have wasted so much time. 浪费了这么多时间，真是遗憾。 [发现2]当不定式短语较长时，通常用it作形式主语，把不定式移到谓语之后，平衡句子结构。 [高考例句] ①It's not a simple matter to determine the nature of talent. 确定天才的本性并不是一件简单的事情。 ②The host will like it if you have learned to use chopsticks. 如果你学会了用筷子，主人会喜欢的。 it是形式主语，真正的主语是后面的动词不定式短语 it作形式宾语，if从句作真正的宾语 2.动词不定式作宾语 [观察1] Father likes to listen to music in silence. 父亲喜欢静静地听音乐。 He prefers to be starved to death rather than beg. 他宁愿饿死也不愿乞讨。 [发现1]不定式可以充当部分及物动词的宾语。 [观察2] We meant to have stayed there a week. 我们原打算在那儿待一个星期的。 I wanted to have dropped her a line, but forgot to do so. 我原想写一个便条给她，但忘记了。 [发现2]在表示“希望、打算”等动词(如hope, expect, intend, mean, want, forget等)的过去式后，可接动词不定式的完成式来表示没有实现的动作。 [观察3] The teacher made no comments except to tell him to work hard. 老师除了叫他努力学习外，未做任何评价。 He had no choice but to sit there as usual. 他没有选择，只好像往常一样坐在那儿。 [发现3]不定式可以作介词but和except的宾语。 [观察4] I found it possible to work out the problem without a computer. 我发现有可能不用计算机而解出这道题目。 [发现4]在feel, find, make, think, consider等动词后，如果宾语带有宾语补足语，人们常常用it作形式宾语，而把真正的宾语放在宾语补足语之后。 [高考例句] ①New technologies have made it possible to turn out new products faster and at a lower cost. 新技术使得以更快的速度且更低的价格生产新产品成为可能。 ②The friends who introduced me to camping thought that it meant to be a pioneer. 让我了解了露营的朋友们认为露营就意味着要成为一个开拓者。 ③Depending on which role you choose, you could help to increase a community's access to safe drinking water, or help to protect valuable local cultures. 根据您所选择的角色，您可以帮助增加社区获得安全饮用水的机会，或者帮助保护有价值的当地文化。 ④If he takes on this work, he will have no choice but to meet an even greater challenge. 如果他承担这项工作，他将别无选择，只有面对甚至更大的挑战。 提示：it作形式宾语，真正的宾语是不定式短语 提示：mean to do...注定做…… 3.动词不定式作定语 [观察1] The future to greet us will