Unit 7 How do things change 寒假预习（讲义）-2025-2026学年沪教版英语四年级下册

U7 How do things change? 单元核心知识点讲解 （一）重点单词 1. 物质状态类：liquid 液体、solid 固体、gas 气体、steam 水蒸气 2. 食材与物品类：sugar 食糖、salt 盐；食盐、cream 奶油、ice 冰、chocolate 巧克力、plastic 塑料的、mixture 混合物、freezer 冰柜、pot 锅、bag 袋子 3. 动作类：melt （使）熔化；融化、freeze 结冰；冻住、mix （使）混合、heat 加热、shake 摇动、put 放、add 增加；添加、cook 烹饪 4. 描述与常用类：hungry 感到饿的、busy 忙碌的、open 开着的；敞开的、different 不同的、same 相同的、party 聚会；派对、idea 想法 （二）重点短语 1. melt down 熔化；融化2. freeze into 冻结成3. mix...with... 把……和……混合 4. heat up 加热5. shake well 摇匀6. add...to... 把……添加到…… 7. make a mixture 制作混合物8. turn into 变成9. in the freezer 在冰柜里 （三）重点句型 1. 询问是否要做某事（提议）：--Shall we...? --Sure! / Good idea! 例：—Shall we make ice cream together? 我们一起做冰淇淋好吗？ —Sure! That's interesting. 当然！太有趣了。 解析：Shall we 后接动词原形，用于提出友好的建议，回答用表示赞同的短语。 2. 表达让我们做某事：Let's... 例：Let's mix sugar and cream first. 我们先把糖和奶油混合起来吧。 解析：Let's 是 Let us 的缩写，后接动词原形，语气亲切，用于提议共同做某事。 3. 描述某物发生变化：...turns into... / ...is changing into... 例：Water turns into ice when it's cold. 天冷时水会变成冰。 The ice is changing into water in the sun. 冰在太阳下正变成水。 解析：turn into 表示“变成”，一般现在时描述客观事实，现在进行时描述正在发生的变化。 4. 表达使用某物做某事：use sth. to do sth. 例：We use ice and salt to freeze the mixture. 我们用冰和盐来冷冻混合物。 解析：use 后接名词作宾语，to 后接动词原形，表目的。 （四）语音重点 发音组合：fr 例词：fruit 水果、friend 朋友、fresh 新鲜的、freeze 结冰、fry 油炸、frame 框架 单元练习题 一、选出划线部分发音不同的一项。 （ ）1. A. fruit B. friend C. clock （ ）2. A. fresh B. fry C. drum （ ）3. A. freeze B. friend C. fly （ ）4. A. frame B. fresh C. flute （ ）5. A. fruit B. drum C. friend 二、根据句意及首字母提示填空。 1. Water is a l______, and ice is a solid. 2. We need to m______ sugar and milk to make the drink. 3. The sun is hot, so the snow is m______ quickly. 4. Put the mixture in the freezer. It will f______ into ice cream soon. 5. Add some s______ to the soup. It will taste better. 三、短语翻译。 1. mix...with... ______ 2. heat up ______ 3. turn into ______ 4. make a mixture ______ 5. shake well ______ 四、选择合适的单词/短语填空（注意形式变化）。 melt freeze mix heat shake add turn into different 1. She ______ some chocolate to the cake. It becomes more delicious. 2. ______ the bottle well before you drink the juice. 3. We need to ______ the water to make tea. 4. When spring comes, the ice ______ into water. 5. ______ sugar with flour, and then we can make cookies. 6. Put the water in the fridge. It will ______ into ice. 7. There are many ______ ways to make fruit salad. 五、单项选择。 （ ）1. —Shall we ______ a fruit mixture? —Good idea! A. make B. makes C. making （ ）2. Water ______ into steam when it boils. A. turn B. turns C. turning （ ）3. We use salt and ice ______ the mixture. A. freeze B. freezing C. to freeze （ ）4. ______ mix the cream and chocolate first. A. Let B. Let's C. Shall we （ ）5. The ice cream ______ because the freezer door is open. A. melts B. is melting C. melted （ ）6. —What are you doing? —I ______ the mixture of milk and sugar. A. shake B. shaking C. am shaking 六、用所给单词的适当形式填空。 1. Look! They ______ (mix) salt and ice in the big bag. 2. My mother usually ______ (heat) the soup before dinner. 3. We ______ (not freeze) the water now. We need to drink it. 4. The chocolate ______ (melt) in the sun if we don't put it in the fridge. 5. Shall we ______ (add) some strawberries to the ice cream? 七、按要求完成句子。 1. We make ice cream with cream and sugar.（对划线部分提问） ______ do you make ice cream ______? 2. Shall we shake the bag?（改为同义句） ______ ______ shake the bag? 3. Water turns into ice in the freezer.（改为一般疑问句） ______ water ______ into ice in the freezer? 4. The mixture is freezing.（改为否定句） The mixture ______ ______. 5. They are mixing salt and ice.（对划线部分提问） ______ are they ______? 八、选择合适的句子补全对话。 A: Hi, Tom! Do you want to make ice cream with me?A. What do we need? B. Shall we mix them first? C. How do we make it? D. Put the small bag into the big bag. E. Then shake the big bag for 5 minutes. B: Yes! That's fun. 1. ______ A: We need cream, sugar, salt, ice and two plastic bags. B: I have them all. 2. ______ A: First, mix cream and sugar in the small bag. B: 3. ______ A: Yes, make sure they are well mixed. 4. ______ B: OK. The big bag has ice and salt. A: 5. ______ Then we can have ice cream. B: Great! Let's do it. 九、根据短文内容，完成下列任务。 Everything in our world is a solid, liquid or gas. Ice, metal and stone are solids. They have a fixed shape. Water, milk and juice are liquids. They can flow and take the shape of the container. Air, steam and oxygen are gases. We can't see most gases easily. Things can change from one state to another. When we heat water, it turns into steam (gas). When we cool water, it turns into ice (solid). When the temperature rises, ice melts into water (liquid). We can use these changes to make many things, like ice cream, juice and soup. 任务一：阅读短文，补全句子（每空一词）。 1. Solids have a ______ shape, and liquids can ______. 2. When the temperature rises, ice ______ into water. 任务一：阅读短文，回答问题。 1. What are the three states of matter mentioned in the passage? ___________________________________ 2. How does water turn into steam? ___________________________________ 参考答案 一、1. C 2. C 3. C 4. C 5. B 二、1. liquid 2. mix 3. melting 4. freeze 5. salt 三、1. 把……和……混合 2. 加热 3. 变成 4. 制作混合物 5. 摇匀 四、1. adds 2. Shake 3. heat 4. turns into 5. Mix 6. freeze 7. different 五、1. A 2. B 3. C 4. B 5. B 6. C 六、1. are mixing 2. heats 3. aren't freezing 4. will melt 5. add 七、1. What；with 2. Let's 3. Does；turn 4. isn't freezing 5. What；doing 八、1. A 2. C 3. B 4. D 5. E 九、任务一：1. fixed；flow 2. melts 任务二：1. Solid, liquid and gas. 2. By heating it. 学科网（北京）股份有限公司 $