Unit5知识点 Grammar-2025-2026学年人教版八年级英语下册

八年级英语下册Unit5知识点-Grammar语法 学习目标 1. 掌握 enough 的用法： - enough 修饰名词时放在名词前； - enough 修饰形容词或副词时放在其后； - 掌握“形容词 + enough + to do”结构。 2. 掌握 too ... to ... 的用法： - too 修饰形容词或副词，表示“太……”； - “too + 形容词/副词 + to do”表示“太……而不能……”； - 学会用 for + 宾语 引出不定式的逻辑主语。 3. 理解 too ... to ... 与 not + 形容词反义词 + enough to ... 的转换关系。 4. 能在具体语境中正确运用 enough 和 too ... to 结构。 第一部分：enough 的用法 一、enough 作形容词修饰名词 enough 可以放在复数名词或不可数名词前，表示“足够的，充足的”。 结构公式：enough + 名词 例句： - There is enough room for you. （有足够的地方给你。） - Do we have enough time? （我们有足够的时间吗？） - He has enough money to buy a car. （他有足够的钱买一辆车。） 挖空练习：用 enough + 适当名词填空。 1. We don’t have ________ ________ (足够的水) for the trip. 2. Are there ________ ________ (足够的椅子) for everyone? 二、enough 修饰形容词或副词 当 enough 修饰形容词或副词时，必须放在形容词或副词之后。 结构公式：形容词/副词 + enough 例句： - The room is big enough. （这个房间足够大。） - He runs fast enough. （他跑得够快。） 挖空练习：将 enough 放在正确的位置。 1. The box is light. (enough) → The box is ________ ________. 2. She speaks clearly. (enough) → She speaks ________ ________. 三、“be + 形容词 + enough + to do”结构 这个结构用来描述一个人的品质或能力，表示“足够……可以做某事”。 结构公式：主语 + be + 形容词 + enough + to do sth. 例句： - Confucius is wise enough to be one of the greatest ancient Chinese thinkers. （孔子十分睿智，是中国古代最伟大的思想家之一。） - The girl is not brave enough to go near the dog. （这个女孩胆子不够大，不敢靠近那只狗。） - He is old enough to go to school. （他够上学的年龄了。） 挖空练习：用所给词完成句子。 1. She is ________ ________ (够聪明) to solve the problem. 2. The boy is ________ ________ ________ (不够强壮) to carry the box. 第二部分：too ... to ... 的用法 一、too 修饰形容词或副词 too 放在形容词或副词前，表示“太，过于，过度”。 结构公式：too + 形容词/副词 例句： - This bag is too heavy for me. （这个包对我而言太沉了。） - He walks too slowly. （他走得太慢了。） 挖空练习：用 too + 所给词填空。 1. The coffee is ________ ________ (太烫) to drink. 2. She speaks ________ ________ (太快). I can’t follow her. 二、“be + too + 形容词 + to do”结构 这个结构表达一个否定的结果，表示“太……而不能做某事”。 结构公式：主语 + be + too + 形容词 + to do sth. 例句： - He is too tired to go swimming. （他太累了，没法去游泳了。） - The water is too hot to drink. （水太烫了，还不能喝。） 挖空练习：用 too ... to ... 完成句子。 1. The box is ________ ________ ________ ________ (太重搬不动). 2. She is ________ ________ ________ ________ (太害羞不敢发言) in class. 三、用 for 引出逻辑主语 当需要明确指出不定式的逻辑主语时，可以在不定式前加 for + 宾语。 结构公式：主语 + be + too + 形容词 + for + 宾语 + to do 例句对比： - The box is very heavy. The little boy cannot carry it. → The box is too heavy for the little boy to carry. - The apple is very high. The child cannot reach it. → The apple is too high for the child to reach. 挖空练习：用 too ... for ... to ... 合并句子。 1. The problem is very difficult. I cannot solve it. → The problem is ________ ________ ________ ________ ________. 2. The book is very boring. He doesn’t want to read it. → The book is ________ ________ ________ ________ ________. 四、动词不定式的及物性 在 too ... to ... 结构中，如果不定式中的动词是及物动词，它后面通常要带宾语；如果是不及物动词，则不带宾语。 例句： - He is too tired to go any further. （go 是不及物动词，不带宾语） - She is too shy to share her ideas with her classmates. （share 是及物动词，带宾语 her ideas） 五、特殊用法：never ... too ... to ... 当 too ... to ... 结构与 never 连用时，不再表示否定，而表示肯定意义。 例句： - One is never too old to learn. （活到老，学到老。） 六、too ... to ... 与 not ... enough to ... 的转换 “be + too + 形容词 + to do” 可以转换为 “be + not + 形容词反义词 + enough + to do”。 例句： - The little girl is too young to go to school. = The little girl is not old enough to go to school. （这个小女孩年纪太小，还不能上学。） 转换规则：将 too 后面的形容词换成它的反义词，并用否定形式。 常见反义词对： - young ⇔ old - short ⇔ tall - weak ⇔ strong - light ⇔ heavy - cheap ⇔ expensive 挖空练习：将下列句子转换为 not ... enough to ... 结构。 1. The water is too dirty to drink. → The water is ________ ________ ________ ________ drink. 2. He is too weak to carry the box. → He is ________ ________ ________ ________ carry the box. 第三部分：enough 与 too 的位置总结 结构 位置 例句 enough + 名词 enough 放在名词前 We have enough time. 形容词/副词 + enough enough 放在形容词/副词后 He is tall enough. too + 形容词/副词 too 放在形容词/副词前 It is too hot. 请补全下列规则： - The word enough is used ________ (before, after) a noun, but ________ (before, after) an adjective or adverb. - The word too is used ________ (before, after) an adjective or adverb. 第四部分：配套练习 A. 单项选择 ( ) 1. The boy is _______ to go to school.  A. enough old B. old enough C. too old D. so old ( ) 2. The soup is _______ hot for me to drink.  A. too B. enough C. very D. so ( ) 3. We don’t have _______ for everyone.  A. enough chairs B. chairs enough C. too chairs D. chairs too ( ) 4. She is _______ shy _______ speak in public.  A. too; to B. enough; to C. so; that D. very; to ( ) 5. The box is too heavy _______ the little boy _______ carry.  A. for; to B. to; for C. of; to D. to; of ( ) 6. One is never _______ old _______ learn.  A. too; to B. enough; to C. so; that D. very; to B. 用 enough 或 too 填空 1. Please wait patiently ________ to let everyone get their turn. 2. Don’t talk ________ loudly. Keep quiet. 3. Take ________ food to feel full. Don’t take ________ much. 4. Don’t blow on your food if it is ________ hot. 5. Make sure the table is clean ________ for others to use. 6. Clear your plates to make ________ space for others. C. 用所给词的正确形式完成句子（enough to 或 too ... to） 1. patient / listen / carefully / when the students speak → Mrs Li is ________ ________ ________ ________ carefully when the students speak. 2. brave / share his ideas → He is ________ ________ ________ ________ his ideas. 3. excited / express himself / clearly → He is ________ ________ ________ ________ himself clearly. 4. busy / hear Suzy’s opinion → She is ________ ________ ________ ________ Suzy’s opinion. 5. creative / draw / so many amazing pictures → The artist is ________ ________ ________ ________ so many amazing pictures. 6. shy / join the discussion → The girl is ________ ________ ________ ________ the discussion. D. 完成关于历史人物的故事（用 too ... to 或 enough to） 1. Ji Bu was very popular. He was ________ (trustworthy, win) others’ praise. 2. The old woman was ________ (poor, buy) food for herself, so she often beat down fruits from Du Fu’s tree. 3. Du Fu knew about this but he was ________ (kind, stop) her. 4. The travellers were all ________ (thirsty, walk) any further. They found a pear tree and ate the pears. 5. Xu Heng was ________ (honest, take) others’ things, even though no one knew who the tree belonged to. E. 句型转换（每空一词） 1. The water is too dirty to drink. → The water is ________ ________ ________ ________ drink. 2. He is too weak to carry the box. → He is ________ ________ ________ ________ carry the box. 3. The girl is old enough to go to school. → The girl is ________ ________ ________ go to school. （用 too ... to 改写，注意形容词反义词） 4. The box is so heavy that the boy can’t carry it. → The box is ________ heavy ________ the boy ________ carry. F. 翻译句子 1. 他有足够的钱买那辆车。 → He has ________ ________ ________ buy that car. 2. 这个女孩不够勇敢，不敢在课堂上发言。 → The girl is ________ ________ ________ ________ speak in class. 3. 这个问题太难了，我回答不了。 → This question is ________ ________ ________ me ________ answer. 4. 他跑得不够快，追不上公交车。 → He doesn’t run ________ ________ ________ catch the bus. 5. 活到老，学到老。 → One is ________ ________ ________ ________ learn. 参考答案 A. 单项选择 1. B（old enough 足够大） 2. A（too ... to ...） 3. A（enough + 名词） 4. A（too ... to ...） 5. A（for sb. to do sth.） 6. A（never too old to learn） B. enough / too 填空 1. enough 2. too 3. enough; too 4. too 5. enough 6. enough C. enough to / too ... to 完成句子 1. patient enough to listen 2. brave enough to share 3. too excited to express 4. too busy to hear 5. creative enough to draw 6. too shy to join D. 历史人物故事 1. trustworthy enough to win 2. too poor to buy 3. too kind to stop 4. too thirsty to walk 5. too honest to take E. 句型转换 1. not clean enough to 2. not strong enough to 3. too young to 4. too; for; to F. 翻译 1. enough money to 2. not brave enough to 3. too difficult for; to 4. fast enough to 5. never too old to 1 学科网（北京）股份有限公司 $