Unit 3 Happy together专项练习含知识梳理及详细解析（专项训练）-2026-2027学年外研版（三起）英语五年级上册

**基本信息** 聚焦单元核心知识点，通过分层训练与情境化辨析，系统构建从词汇到语法的知识逻辑，提炼实用解题方法，提升语言能力与思维品质。 **专项设计** |模块|题量/典例|方法提炼|知识逻辑| |----|-----------|----------|----------| |10个重点易错考点|90题（基础/提升/拓展三级）|分层突破（基础应用→情境辨析→逻辑推理）；语法规则归纳（如频度副词位置、连词用法）；情境化解题技巧（如情感形容词匹配语境）|从核心词汇（情感/性格形容词）→短语（with搭配）→句型（Why问句、祈使句）→语法（连词、情态动词should）递进，形成“词汇-句型-语法-综合交际”完整链条|

外研版（三起）五年级上册 Unit 3 Happy together 专项练习 最新外研版（三起）五年级上册 Unit 3 Happy together 专项练习（含知识梳理及详细解析） 📚 第一部分：单元重点知识梳理（中英对照） 【重点单词】 英文 中文 英文 中文 friendship 友谊 unhappy 不开心 both 两者都 funny 有趣的 musical 擅长音乐的 difference 差异 rabbit 兔 key 关键 similar 相似的 openly 坦诚地 share 分享 miss 想念 trust 信任 celebrate 庆祝 fight / argue 争吵 solve 解决 kind 友善的 polite 有礼貌的 smile 微笑 laugh 大笑 support 支持 care 关心 team 团队 teamwork 团队合作 【重点短语】 英文 中文 英文 中文 help each other 互相帮助 share things 分享东西 talk to each other 互相交谈 be happy for each other 为彼此开心 take care of each other 互相照顾 play together 一起玩 have fun 玩得开心 make friends 交朋友 talk openly 坦诚沟通 solve problems 解决问题 argue with sb. 和某人争吵 say sorry to sb. 向某人道歉 work in a team 团队合作 care about sb. 关心某人 【重点句型】 英文 中文 We play together and have fun. 我们一起玩，很开心。 We are different but we are friends. 我们不一样，但我们是朋友。 I'm happy because you are my friend. 我很开心因为你是我的朋友。 Why are you unhappy? 你为什么不开心？ What are your friends like? 你的朋友们是什么样的？ We both like reading. 我们两个都喜欢阅读。 Don't fight with your classmates. 不要和同学打架。 Can I help you? 我能帮你吗？ That's OK. / That's all right. 没关系。 Let's be friends again. 我们再做朋友吧。 【重点语法】 语法点 用法说明 例句 and / but / because and并列；but转折；because原因 I like tea but he likes coffee. Why 引导的特殊疑问句 Why + 一般疑问句？ Because... Why are you sad? Because I lost my book. should / shouldn't + 动词原形 提建议，无人称变化 You should be kind to your friends. both 表示两者都 both 放 be 后/实义动词前 We both like music. / They are both tall. 频度副词 always>usually>often>sometimes>never She usually gets up at 7. 祈使句 动词原形开头表指令；Don't + 原形表禁止 Be quiet. / Don't shout. 介词 with 的搭配 play with / share with / talk with / argue with Don't argue with your friends. ✏️ 第二部分：10个重点易错考点专项练习（90题·全选择题） 考点1：考点一：核心情感与性格形容词辨析——unhappy / sad / worried / afraid / sorry / kind / polite / funny / musical / similar 基础题（选择题） ◇（ ）1. Olivia lost her pen. She feels ____. A. happy B. unhappy C. funny D. polite 📝 Olivia丢了她的笔。她感到____。 ◇（ ）2. Jam's dog is ill. He is very ____. A. afraid B. worried C. kind D. sad 📝 Jam的狗生病了。他非常____。 ◇（ ）3. Chen Wei broke a cup. He says ‘I'm ____.’ A. sorry B. angry C. tired D. hungry 📝 Chen Wei打碎了一个杯子。他说“我很____。” 提升题（选择题） ▷（ ）1. Lily always says ‘please’ and ‘thank you’. She is very ____. A. rude B. polite C. shy D. busy 📝 Lily总是说“请”和“谢谢”。她非常____。 ▷（ ）2. Zhou Kai likes telling jokes. He is a ____ boy. A. boring B. funny C. angry D. quiet 📝 Zhou Kai喜欢讲笑话。他是一个____的男孩。 ▷（ ）3. Bella plays the piano well. She is ____. A. sporty B. musical C. lazy D. noisy 📝 Bella钢琴弹得很好。她很____。 拓展题（选择题） ★（ ）1. Which word means ‘not different from’? ____ A. same B. similar C. special D. strange 📝 哪个词意思是“与……相似”？ ★（ ）2. Zhang Hao is afraid of the dark. ‘Afraid’ means ____. A. scared B. happy C. brave D. excited 📝 Zhang Hao怕黑。“Afraid”意思是____。 ★（ ）3. Olivia and Jam like the same music. They have ____ tastes. A. different B. similar C. opposite D. strange 📝 Olivia和Jam喜欢同样的音乐。他们有____品味。 考点2：考点二：频度副词辨析与位置——always / usually / often / sometimes / never 基础题（选择题） ◇（ ）1. I ____ eat breakfast. (every day without fail) A. never B. sometimes C. always D. seldom 📝 我____吃早餐。（每天从不间断） ◇（ ）2. She ____ goes to the park at weekends. (most of the time) A. never B. usually C. hardly D. once 📝 她周末____去公园。（大多数时候） ◇（ ）3. They ____ play football after school. (from time to time) A. often B. always C. never D. sometimes 📝 他们放学后____踢足球。（时不时） 提升题（选择题） ▷（ ）1. Which adverb means ‘not ever’? ____ A. always B. often C. never D. usually 📝 哪个副词意思是“从未”？ ▷（ ）2. Jam says: ‘I ____ eat candy because it's bad for teeth.’ A. always B. usually C. never D. often 📝 Jam说：“我____吃糖果因为对牙齿不好。” ▷（ ）3. Where do we put ‘usually’? ‘I ____ get up at 7.’ A. before I B. after get C. after I D. at the end 📝 ‘usually’应该放在句子的哪个位置？“我____7点起床。” 拓展题（选择题） ★（ ）1. Put the words in order: ‘She / often / helps / her mum.’ Which is correct? A. She often helps her mum. B. She helps often her mum. C. Often she helps her mum. D. She helps her often mum. 📝 排列正确顺序。哪个是正确的？ ★（ ）2. Chen Wei says: ‘I am ____ late for school.’ (not late, not never) A. always B. never C. seldom D. usually 📝 Chen Wei说：“我____迟到。”（不常迟到） ★（ ）3. Which sentence is CORRECT? ____ A. He never is angry. B. He is never angry. C. Never he is angry. D. He is angry never. 📝 哪个句子是正确的？ 考点3：考点三：连词 and / but / because 的辨析与运用 基础题（选择题） ◇（ ）1. We play together ____ have fun. (adding information) A. but B. because C. and D. or 📝 我们一起玩____很开心。（补充信息） ◇（ ）2. I like apples ____ my brother likes oranges. (contrast) A. and B. but C. because D. so 📝 我喜欢苹果____我弟弟喜欢橘子。（对比） ◇（ ）3. She is happy ____ she got a new friend. (reason) A. and B. but C. because D. or 📝 她很开心____她交了一个新朋友。（原因） 提升题（选择题） ▷（ ）1. Olivia is good at singing ____ she practises every day. A. and B. but C. because D. or 📝 Olivia唱歌很好____她每天都练习。 ▷（ ）2. Jam wants to join the team ____ he is not good at sports. A. and B. but C. because D. so 📝 Jam想加入队伍____他不擅长运动。 ▷（ ）3. Lily helps her mum ____ she loves her family. A. but B. and C. because D. or 📝 Lily帮妈妈____她爱她的家人。 拓展题（选择题） ★（ ）1. Which sentence uses ‘but’ CORRECTLY? ____ A. I like tea but he likes coffee. B. I like tea and but he likes coffee. C. I like tea but and he likes coffee. D. I like tea or but he likes coffee. 📝 哪个句子正确使用“but”？ ★（ ）2. Complete: ‘He is tired ____ he still keeps working.’ A. and B. because C. but D. so 📝 完成句子：“他很累____他仍然坚持工作。” ★（ ）3. Which pair can be joined by ‘because’? ____ A. It is sunny. I wear a coat. B. I wear a coat. It is cold. C. I like reading. My brother likes sports. D. She is tall. He is short. 📝 哪两个句子可以用“because”连接？ 考点4：考点四：should / shouldn't + 动词原形（提建议，无人称变化） 基础题（选择题） ◇（ ）1. You ____ be kind to your friends. A. should B. shouldn't C. are D. is 📝 你____对你的朋友友善。 ◇（ ）2. You ____ fight with your classmates. A. should B. shouldn't C. can D. are 📝 你____和同学打架。 ◇（ ）3. We ____ help each other at school. A. shouldn't B. should C. is D. are 📝 我们____在学校互相帮助。 提升题（选择题） ▷（ ）1. Olivia is unhappy. She ____ talk to her friend. A. shouldn't B. should C. is D. are 📝 Olivia不开心。她____和她的朋友谈谈。 ▷（ ）2. Jam and Chen Wei argue. They ____ say sorry to each other. A. shouldn't B. should C. is D. was 📝 Jam和Chen Wei吵架了。他们____互相道歉。 ▷（ ）3. Lily feels lonely. She ____ stay at home all day. A. should B. shouldn't C. is D. are 📝 Lily感到孤独。她____整天待在家里。 拓展题（选择题） ★（ ）1. Which sentence is CORRECT? ____ A. He should plays football. B. She should to study hard. C. We should listen to our teacher. D. They should studying hard. 📝 哪个句子是正确的？ ★（ ）2. Zhang Hao says: ‘If you are angry, you ____ hit anyone.’ A. should B. shouldn't C. can D. are 📝 Zhang Hao说：“如果你生气，你____打任何人。” ★（ ）3. Bella gives advice: ‘You ____ always share your toys with friends.’ A. shouldn't B. should C. are D. is 📝 Bella给出建议：“你____总是和朋友分享你的玩具。” 考点5：考点五：Why引导的特殊疑问句及回答（because引导原因） 基础题（选择题） ◇（ ）1. —____ are you sad? —Because I lost my book. A. What B. Who C. Why D. Where 📝 —____你难过？—因为我丢了书。 ◇（ ）2. —Why is he happy? —____ he won the game. A. Because B. And C. But D. So 📝 —他为什么开心？—____他赢了比赛。 ◇（ ）3. —Why do they like music? —____ it is fun. A. But B. Because C. And D. Or 📝 —他们为什么喜欢音乐？—____它很有趣。 提升题（选择题） ▷（ ）1. Olivia asks Jam: ‘____ are you late?’ Jam answers: ‘Because my bike is broken.’ A. What B. Why C. Who D. Where 📝 Olivia问Jam：‘____你迟到了？’Jam回答：‘因为我的自行车坏了。’ ▷（ ）2. Chen Wei says: ‘I am tired.’ Lily asks: ‘____?’ Chen Wei: ‘Because I ran a lot.’ A. What are you B. Why are you tired C. Who is tired D. Where are you 📝 Chen Wei说：‘我很累。’Lily问：‘____？’ ▷（ ）3. Which answer does NOT match ‘Why are you angry?’ A. Because you broke my toy. B. Because I failed the test. C. I am ten years old. D. Because she lied to me. 📝 哪个回答与“你为什么生气？”不匹配？ 拓展题（选择题） ★（ ）1. Which dialogue is LOGICAL? ____ A. A: Why do you like cakes? B: I am a student. B. A: Why is she smiling? B: Because she got a present. C. A: Why are they noisy? B: They are in the library. D. A: Why do you run? B: I don't like sports. 📝 哪个对话是合理的？ ★（ ）2. Complete: A: ‘____ does he help others?’ B: ‘Because he is kind.’ A. What B. Who C. Why D. Where 📝 完成对话：A：‘____他帮助别人？’B：‘因为他很善良。’ ★（ ）3. Zhou Kai asks: ‘Why don't you play with us?’ Bella: ‘____ I have too much homework.’ A. And B. But C. Because D. So 📝 Zhou Kai问：‘你为什么不跟我们一起玩？’Bella：‘____我有太多作业。’ 考点6：考点六：both 的用法与 both of + 复数名词/代词 基础题（选择题） ◇（ ）1. Olivia and Lily ____ like reading. A. both B. all C. every D. each 📝 Olivia和Lily____喜欢阅读。 ◇（ ）2. ____ of them are good at maths. A. All B. Both C. Every D. Each 📝 他们____两个数学都很好。 ◇（ ）3. We ____ love animals. A. all B. both C. every D. each 📝 我们____热爱动物。 提升题（选择题） ▷（ ）1. Jam and Chen Wei are ____ from Kunming. A. all B. both C. every D. each 📝 Jam和Chen Wei____来自昆明。 ▷（ ）2. ____ of my parents like cooking. A. All B. Both C. Every D. Each 📝 我父母____喜欢做饭。 ▷（ ）3. Which is CORRECT? ‘They are ____ pupils.’ A. all B. both C. every D. each 📝 哪个是正确的？‘他们都是小学生。’ 拓展题（选择题） ★（ ）1. Which sentence is WRONG? ____ A. Both of them are tall. B. They both like music. C. Both she and he are students. D. Both of them is tall. 📝 哪个句子是错误的？ ★（ ）2. Zhang Hao says: ‘My sister and I ____ enjoy painting.’ A. all B. both C. every D. each 📝 Zhang Hao说：‘我妹妹和我____喜欢画画。’ ★（ ）3. Bella and Olivia are friends. ____ of them love dancing. A. All B. Both C. Every D. Each 📝 Bella和Olivia是朋友。她们____都喜欢跳舞。 考点7：考点七：祈使句（肯定动词原形 / 否定 Don't + 动词原形） 基础题（选择题） ◇（ ）1. ____ quiet in the library. A. Be B. Don't be C. To be D. Being 📝 在图书馆请____安静。 ◇（ ）2. ____ shout in the classroom. A. Do B. Be C. Don't D. Not 📝 ____在教室里大喊。 ◇（ ）3. ____ your friend when he is sad. A. Don't help B. Help C. To help D. Helping 📝 当他难过时____你的朋友。 提升题（选择题） ▷（ ）1. Olivia says to Jam: ‘____ angry with me.’ A. Don't be B. Be not C. Not be D. Don't to be 📝 Olivia对Jam说：‘____生我的气。’ ▷（ ）2. The teacher says: ‘____ to each other nicely.’ A. Don't talk B. Talk C. To talk D. Talking 📝 老师说：‘请友好地____彼此。’ ▷（ ）3. Chen Wei tells Lily: ‘____ your room tidy.’ A. Don't keep B. Keep C. To keep D. Keeping 📝 Chen Wei告诉Lily：‘____你的房间整洁。’ 拓展题（选择题） ★（ ）1. Which is a correct imperative sentence? ____ A. You should study hard. B. Please open the window. C. He is running fast. D. They are playing football. 📝 哪个是正确的祈使句？ ★（ ）2. Which is a correct NEGATIVE imperative? ____ A. You don't eat too much. B. Don't eat too much candy. C. He doesn't run in the hall. D. They aren't late for school. 📝 哪个是正确的否定祈使句？ ★（ ）3. Zhou Kai says: ‘____ late for school again!’ A. Don't be B. Be not C. Not be D. Don't to be 📝 Zhou Kai说：‘____再迟到了！’ 考点8：考点八：介词 with 的常用搭配——play with / share with / talk with / argue with 基础题（选择题） ◇（ ）1. I like to play ____ my little brother. A. to B. with C. for D. at 📝 我喜欢____我的小弟弟玩。 ◇（ ）2. We should share our toys ____ our friends. A. to B. with C. for D. at 📝 我们应该____我们的朋友分享玩具。 ◇（ ）3. Don't argue ____ your classmates. A. to B. with C. for D. at 📝 不要____你的同学争吵。 提升题（选择题） ▷（ ）1. Olivia talks ____ her mum about school every day. A. to B. with C. for D. at 📝 Olivia每天都____她妈妈谈论学校。 ▷（ ）2. Jam shares his lunch ____ Bella. A. to B. with C. for D. at 📝 Jam____Bella分享他的午餐。 ▷（ ）3. Chen Wei never fights ____ his brother. A. to B. with C. for D. at 📝 Chen Wei从不____他弟弟打架。 拓展题（选择题） ★（ ）1. Which sentence is CORRECT? ____ A. She plays to her doll. B. She plays with her doll. C. She plays for her doll. D. She plays at her doll. 📝 哪个句子是正确的？ ★（ ）2. Lily says: ‘I want to share this cake ____ you.’ A. to B. with C. for D. at 📝 Lily说：‘我想____你分享这块蛋糕。’ ★（ ）3. Zhang Hao says: ‘Don't argue ____ me. I am your friend!’ A. to B. with C. for D. at 📝 Zhang Hao说：‘不要____我争吵。我是你的朋友！’ 考点9：考点九：描述朋友异同的句型——I like… but my friend likes… / We both like… 基础题（选择题） ◇（ ）1. I like singing ____ my friend likes dancing. A. and B. but C. because D. so 📝 我喜欢唱歌____我的朋友喜欢跳舞。 ◇（ ）2. We ____ like reading books. A. both B. all C. every D. each 📝 我们____喜欢读书。 ◇（ ）3. She enjoys art ____ he enjoys science. A. and B. but C. because D. so 📝 她喜欢美术____他喜欢科学。 提升题（选择题） ▷（ ）1. Olivia likes cats ____ Jam likes dogs. A. and B. but C. because D. so 📝 Olivia喜欢猫____Jam喜欢狗。 ▷（ ）2. Chen Wei and Zhang Hao ____ enjoy playing basketball. A. all B. both C. every D. each 📝 Chen Wei和Zhang Hao____喜欢打篮球。 ▷（ ）3. Lily says: ‘I am quiet ____ my sister is outgoing.’ A. and B. but C. because D. so 📝 Lily说：‘我文静____我妹妹外向。’ 拓展题（选择题） ★（ ）1. Which sentence shows a DIFFERENCE between two friends? ____ A. We both like music. B. I like tea but she likes coffee. C. Both of them are tall. D. They all enjoy sports. 📝 哪个句子展示了两个朋友之间的不同？ ★（ ）2. Bella says: ‘My best friend and I ____ love chocolate.’ A. all B. both C. every D. each 📝 Bella说：‘我最好的朋友和我____喜欢巧克力。’ ★（ ）3. Zhou Kai says: ‘I am good at maths ____ he is good at English.’ A. and B. but C. because D. so 📝 Zhou Kai说：‘我擅长数学____他擅长英语。’ 考点10：考点十：综合交际——解决朋友间矛盾、表达感受、给出建议 基础题（选择题） ◇（ ）1. Your friend is crying. You say: ‘What's wrong? Are you ____?’ A. happy B. sad C. excited D. bored 📝 你的朋友在哭。你说：‘怎么了？你____吗？’ ◇（ ）2. Your friend says ‘I'm sorry.’ You reply: ‘That's ____.’ A. bad B. OK C. wrong D. sad 📝 你的朋友说‘对不起’。你回答：‘没关系。’ ◇（ ）3. You want to help your friend. You say: ‘Can I ____ you?’ A. hurt B. help C. leave D. forget 📝 你想帮助你的朋友。你说：‘我能____你吗？’ 提升题（选择题） ▷（ ）1. Olivia and Jam had a fight. Olivia says: ‘I am ____. Let's be friends again.’ A. angry B. sorry C. happy D. proud 📝 Olivia和Jam吵架了。Olivia说：‘我很____。我们再做朋友吧。’ ▷（ ）2. Chen Wei feels lonely. His mum says: ‘You ____ make some new friends.’ A. shouldn't B. should C. can't D. is 📝 Chen Wei感到孤独。他妈妈说：‘你____交一些新朋友。’ ▷（ ）3. Lily is worried about a test. Zhou Kai says: ‘Don't ____. You can do it!’ A. smile B. worry C. laugh D. sing 📝 Lily担心考试。Zhou Kai说：‘别____。你能行的！’ 拓展题（选择题） ★（ ）1. Which dialogue is the MOST polite and friendly? ____ A. A: Go away! B: OK. B. A: Can I play with you? B: Sure! Come and join us. C. A: You are wrong! B: No, I'm not! D. A: I don't like you. B: I don't care. 📝 哪个对话最有礼貌和最友好？ ★（ ）2. Zhang Hao and Bella are solving a problem. Which order is BEST? ____ A. A: Argue. B: Shout. C: Leave. B. A: Talk calmly. B: Listen. C: Find a solution together. C. A: Cry. B: Run away. C: Ignore. D. A: Fight. B: Complain. C: Give up. 📝 Zhang Hao和Bella在解决问题。哪个顺序最好？ ★（ ）3. Complete: A: ‘I failed the test.’ B: ‘____. Try again! You can do better.’ A. That's terrible B. It's OK to fail C. You are bad D. Never mind 📝 完成对话：A：‘我考试没及格。’B：‘____。再试一次！你可以做得更好。’ 📝 参考答案与详细解析 考点1： 基础题：B(unhappy) D(sad) A(sorry) 提升题：B(polite) B(funny) B(musical) 拓展题：B(similar) A(scared) B(similar) 【解析】unhappy不开心（丢失东西）；sad难过（他人生病）；sorry抱歉（做错事）；polite有礼貌的（说please/thank you）；funny有趣的（讲笑话）；musical擅长音乐的（弹钢琴）；similar相似的（same taste）；afraid=scared害怕的。 考点2： 基础题：C(always) B(usually) D(sometimes) 提升题：C(never) C(never) C(after I) 拓展题：A(She often helps her mum.) C(seldom) B(He is never angry.) 【解析】always总是（从不间断）> usually通常 > often经常 > sometimes有时 > seldom很少 > never从不；频度副词位置：be动词后，实义动词前；正确语序：She often helps her mum. He is never angry. 考点3： 基础题：C(and) B(but) C(because) 提升题：C(because) B(but) C(because) 拓展题：A(I like tea but he likes coffee.) C(but) B(I wear a coat. It is cold.) 【解析】and表并列（补充信息）；but表转折（前后相反）；because表原因（回答Why）；正确用法：I like tea but he likes coffee. 连接因果：I wear a coat because it is cold. 考点4： 基础题：A(should) B(shouldn't) B(should) 提升题：B(should) B(should) B(shouldn't) 拓展题：C(We should listen to our teacher.) B(shouldn't) B(should) 【解析】should+动词原形（建议应该做）；shouldn't+动词原形（建议不应该做）；无人称变化（I/you/he/we/they都用should）；正确：We should listen. 否定：You shouldn't hit anyone. 考点5： 基础题：C(Why) A(Because) B(Because) 提升题：B(Why) B(Why are you tired) C(I am ten years old.) 拓展题：B(A: Why is she smiling? B: Because she got a present.) C(Why) C(Because) 【解析】Why+一般疑问句询问原因；用Because回答；逻辑匹配：Why is she smiling? Because she got a present. 不逻辑：I am ten years old回答Why are you angry. 考点6： 基础题：A(both) B(Both) A(all) 提升题：B(both) B(Both) A(all) 拓展题：D(Both of them is tall.) B(both) B(Both) 【解析】both指两者都（用于两个人/物）；all指三者及以上都；both位置：be后/实义动词前；Both of them are tall（谓语动词用复数are）；We both like music. 考点7： 基础题：A(Be) C(Don't) B(Help) 提升题：A(Don't be) B(Talk) B(Keep) 拓展题：B(Please open the window.) B(Don't eat too much candy.) A(Don't be) 【解析】祈使句：动词原形开头（肯定）；Don't+动词原形（否定）；Be quiet（be动词原形）；Don't be angry（否定）；正确：Please open the window. Don't eat too much candy. 考点8： 基础题：B(with) B(with) B(with) 提升题：B(with) B(with) B(with) 拓展题：B(She plays with her doll.) B(with) B(with) 【解析】with是介词，表“和…一起/用”；play with和…玩；share with和…分享；talk with和…交谈；argue with和…争吵；全部搭配with，不能换to/for/at. 考点9： 基础题：B(but) A(both) B(but) 提升题：B(but) B(both) B(but) 拓展题：B(I like tea but she likes coffee.) B(both) B(but) 【解析】描述异同：but表转折对比（I like A but he likes B）；both表两者相同（We both like...）；找不同用but；找相同用both. 考点10： 基础题：B(sad) B(OK) B(help) 提升题：B(sorry) B(should) B(worry) 拓展题：B(A: Can I play with you? B: Sure! Come and join us.) B(A: Talk calmly. B: Listen. C: Find a solution together.) B(It's OK to fail) 【解析】交际用语：朋友哭泣→Are you sad?；道歉回应→That's OK. / That's all right.；提供帮助→Can I help you?；争吵后→I'm sorry. Let's be friends again.；鼓励→It's OK to fail. Try again! — 第 页 — 学科网（北京）股份有限公司 $