Unit 4 Grammar-备战2021年中考英语一轮复习九年级全一册知识梳理(人教版)

Unit4 I used to be afraid of the dark Grammar 语法精讲 used to do sth.的用法小结 1. used to do sth.表示“过去常常做某事”，将过去和现在对比，暗示现在不做了。其中，to为动词不定式符号，后接动词原形。 He used to go to school at six o'clock. 他过去常常六点去上学。 2. used to do sth.的否定形式 主语 ＋ usedn’t to do sth. 或 主语 ＋ didn't use to do sth. He used to play computer games all day. 他过去常常整天玩电脑游戏。 →He usedn't to play computer games all day. ＝He didn't use to play computer games all day. 他过去不常整天地玩电脑游戏。 注意: usedn't ＝ used not 3. used to do的疑问句形式及其答语 1) Used ＋ 主语 ＋ to do…？ 回答:Yes，sb. used to. / No，sb. usedn't to. Tom used to watch TV. → Used Tom to watch TV? Yes, he used to. / No, he usedn't to. 2) Did ＋ 主语 ＋ use to do...？ 回答:Yes, sb. did. / No, sb. didn't. I used to do homework after school. → Did you use to do homework after school? Yes, I did. / No, I didn't. 4. used to do的反意疑问句形式也有两种，类似于否定句形式。 —They used to see English movies on Sundays, usedn't they？/ didn't they? —Yes, they used to. / No，they usedn't to.或Yes, they did. / No,they didn't. 5. used to也可用