Unit 2 Great inventions and discoveries 重点单词,词性转换,短语,语法（知识默写+习题训练）-2025-2026学年八年级英语下册单元练习(沪教版五四学制)

班级 姓名 学号 分数 Unit 2 Great inventions and discoveries 单元重点单词变形短语语法句型精练 （时间：60分钟，满分：100分） 单元知识点默写 一、词性转换 1. discovery (n. 发现；发觉) → discover (v. 发现) 2. exploration (n. 探索；勘查) → explore (v. 探索；勘查) 3. economy (n. 经济) → economic (adj. 经济的) 4. illness (n. 疾病，病) → ill (adj. 生病的) 5. socialism (n. 社会主义) → social (adj. 社会的) 6. totally (adv. 全部地；整个地) → total (adj. 全部的；整个的) 7. serious (adj. 严重的；严肃的) → seriously (adv. 严重地；严肃地) 8. medical (adj. 医学的；医疗的) → medicine (n. 药；医学) 9. volunteer (v./n. 自愿做；志愿者) → voluntary (adj. 志愿的；自愿的) 10. herself (pron. 她自己) → she (pron. 她) 二、单词拼写 试卷第1页，共3页 学科网（北京）股份有限公司 1. 发现；发觉 → discovery 2. 古代的；古老的 → ancient 3. 探索；勘查 → exploration 4. 轮子；车轮 → wheel 5. 经济 → economy 6. 材料；原料 → material 7. 渔网 → fishnet 8. 战争 → war 9. （身体或精神上的）疾病，病 → illness 10. 社会主义 → socialism 11. 习惯 → habit 12. 几乎不；几乎没有 → hardly 13. 全部地；整个地 → totally 14. 电话 → telephone 15. （金属、塑料、橡皮制成的）管，管子 → tube 16. 骨头 → bone 17. X射线；X光 → X-ray 18. 颁奖；奖；奖品 → award 19. 爵士；（对不认识男性的尊称）先生 → sir 20. 霉；霉菌 → mould 21. (pl.) 细菌 → bacteria 22. 救命的；救生的 → life-saving 23. 进程；课程 → course 24. 医治；治疗 → treat 25. 严重的；严肃的 → serious 26. 疟疾 → malaria 27. 医学的；医疗的 → medical 28. 自愿做；义务做；无偿做；志愿者 → volunteer 29. （用作女性的反身代词）她自己，自己 → herself 30. 空闲的 → spare 三、短语拼写 1. 偶然；意外地 → by accident 2. 令人惊讶的是 → to one's surprise 3. 使……变成 → turn ... into 4. 使……变亮 → light up 5. 保持联系 → keep in touch 单元知识点习题训练 1、 用括号内所给单词的适当形式填空(本大题共20小题，每小题1分，共20分) 1．She practises ________ (draw) every day to improve her skills. 【答案】drawing 【详解】句意：她每天练习画画来提高她的技能。句中“practise doing sth.”为固定搭配，意为“练习做某事”，practise后接动名词形式，draw的动名词为drawing，故填drawing。 2．The teacher’s ________ (encourage) words made me feel more confident before the exam. 【答案】encouraging 【详解】句意：老师鼓励的话让我在考试前感到更自信。所给单词encourage是动词，意为“鼓励”，根据句子结构，此处需要形容词形式修饰“words”，表示“鼓励的话”，encourage的形容词形式是encouraging，意为“鼓励的、鼓舞人心的”，符合句意。故填encouraging。 3．The wounded were taken to the local hospital by the ________ workers. (medicine) 【答案】medical 【详解】句意：伤员被医务人员送往当地医院。根据“the...workers. ”以及所给单词可知，应填medicine的形容词形式medical“医疗的、医学的”，作定语，修饰后面的名词workers。故填medical。 4．He stopped ________ (smoke) because it was bad for his health. 【答案】smoking 【详解】句意：他戒烟了，因为这对他的健康有害。根据“because it was bad for his health”可知，他停止了“吸烟”这个正在进行的动作。stop doing sth.是固定搭配，表示“停止做某事”，因此smoke需要变为动名词形式。故填smoking。 5．The wheel ________ (change) the way people traveled since it was invented. 【答案】has changed 【详解】句意：自从轮子被发明以来，它改变了人们的出行方式。句中“since it was invented”为现在完成时的标志词，提示动作从过去持续到现在，并对现在有影响，应用现在完成时。change的现在完成时形式是have/has changed，主语“The wheel”是第三人称单数，所以用has changed。 6．He would rather ________ (be) a sculptor than a painter when he grows up. 【答案】be 【详解】句意：他长大后宁愿当雕塑家也不愿当画家。句中“when he grows up”为表示将来的时间状语，但“would rather”后接动词原形表示“宁愿做某事”，不随时间变化改变形式，故填be。 7．I’m sorry I shouted at you just now. I was just feeling ________ (stress). 【答案】stressed 【详解】句意：很抱歉我刚才对你大喊大叫了，我当时只是感到压力很大。句中feeling是系动词，后面需要接形容词作表语，用来描述人的感受。动词stress对应的形容词形式为stressed，意为“感到有压力的、紧张的”，常用来表达人的情绪状态。 8．The room was ________ (total) dark when the lights went out. 【答案】totally 【详解】句意：当灯熄灭的时候，房间里一片漆黑。dark是形容词，要用副词来修饰。total的副词形式是totally。 9．I can ________ (hard) believe what he said. 【答案】hardly 【详解】句意：我几乎不敢相信他说的话。此处需要副词修饰动词“believe”，“hard”对应的副词“hardly”意为“几乎不”，符合语境。 10．________ (social) is an important political idea in some countries. 【答案】Socialism 【详解】句意：在一些国家，社会主义是一种重要的政治思想。此处需要一个名词作主语，social的名词形式是socialism，意为“社会主义”，首字母大写。 11．He was absent from school because of ________ (ill). 【答案】illness 【详解】句意：他因为生病没去上学。句中“because of”为介词短语，后接名词、代词或动名词。ill是形容词，需变为名词形式illness，故填illness。 12．The ________ (wheel) on the old cart are made of wood. 【答案】wheels 【详解】句意：旧手推车上的轮子是由木头制成的。句中“on the old cart”表明是旧手推车上的轮子，根据“are”可知这里应该用名词复数形式，wheel的复数形式是直接加s，故填wheels。 13．They are planning another ________ (explore) to the South Pole. 【答案】exploration 【详解】句意：他们正计划另一次前往南极的探险。不定代词“another”后接名词单数，动词“explore”的名词形式是“exploration”，意为“探险、探索”，故填exploration。 14．The ________ (discover) of the new species surprised the scientists. 【答案】discovery 【详解】句意：新物种的发现使科学家们感到惊讶。句中“The...of the new species”为名词所有格结构，提示此处需要一个名词，discover的名词形式为discovery。 15．The company is ________ considering the young inventor’s creative proposal for a new type of battery. (serious) 【答案】seriously 【详解】句意：公司正在认真考虑这位年轻发明家关于新型电池的创新提议。根据“is”及“considering”提示，此处应填副词修饰动词considering。“serious”为形容词，其副词形式是seriously“认真地”。故填seriously。 16．The discovery of penicillin was a major breakthrough in the ________ of many bacterial infections. (treat) 【答案】treatment 【详解】句意：青霉素的发现是治疗许多细菌感染方面的重大突破。treat意为“治疗”，是动词。根据空前的定冠词the可知，此处指“治疗”这一概念，应用名词形式。故填treatment。 17．The new invention brought significant ________ benefits to the local community by creating many job opportunities. (economy) 【答案】economic 【详解】句意：这项新发明创造了许多就业机会，为当地社区带来了巨大的经济效益。economy“经济”，名词，此处用其形容词形式economic“经济的”修饰名词benefits。 18．Hope everybody can find his own ________ (strong) and make full use of it. 【答案】strength 【详解】句意：希望每个人都能找到自己的优势并充分利用它。his own后接名词，strong是形容词，意为“强大的”，其名词为strength“优势”。 19．The telephone ________ (invent) by Bell; it helped people keep in touch easily. 【答案】was invented 【详解】句意：电话是由贝尔发明的，它帮助人们很容易地保持联系。根据“by Bell”可知，此处表示电话是被贝尔发明的，用被动语态，且描述的是过去发生的事情，用一般过去时的被动语态，其结构为“was/were+过去分词”，主语“The telephone”是单数，be动词用was，invent的过去分词是invented。故填was invented。 20．The volunteers ________ (clean) the art museum when we got there. 【答案】were cleaning 【详解】句意：当我们到达那里时，志愿者们正在打扫艺术博物馆。根据“The volunteers...the art museum when we got there.”可知，本句是含有when引导的时间状语从句的主从复合句，“when”引导的时间状语从句强调一个动作 (got there) 发生，另一个动作 (clean) 正在进行，所以主句应用过去进行时，结构是“was/were+动词的现在分词”，主语“The volunteers”是复数，be动词用were，clean的现在分词是cleaning，故填were cleaning。 二、根据汉语提示完成单词(本大题共10小题，每小题1分，共10分) 21．The students are learning about the ________ (历史) of Chinese art. 【答案】history 【详解】句意：学生们正在学习中国艺术的历史。根据汉语提示可知，history“历史”，不可数名词。故填history。 22．The doctor used a special tool to ________ (检查) the patient’s eyes. 【答案】examine 【详解】句意：医生用一种特殊工具检查病人的眼睛。根据汉语提示可知，examine“检查”，此处用在动词不定式“to examine”中，作目的状语。故填examine。 23．Edison is a famous ________ (发明家) who invented the light bulb. 【答案】inventor 【详解】句意：爱迪生是发明灯泡的著名发明家。inventor“发明家”，a修饰可数名词单数形式。 24．The Internet makes communication more ________ (方便的) than before. 【答案】convenient 【详解】句意：互联网使交流比以前更加方便了。convenient“方便的”，形容词，在句中作宾语补足语。 25．This new technology has a great ________ (影响) on our daily life. 【答案】influence 【详解】句意：这项新技术对我们的日常生活有很大的影响。影响“influence”，可数名词，根据空前有不定冠词a，可知此处应用单数形式influence。 26．The little boy has a ________ (天赋) for music. 【答案】gift/talent 【详解】句意：这个小男孩有音乐天赋。根据汉语提示可知，gift/talent“天赋”，have a gift/talent for“在……方面有天赋”。故填gift/talent。 27．The painting has a ________ (宁静的) atmosphere that makes people feel relaxed. 【答案】peaceful 【详解】句意：这幅画有一种宁静的气氛，让人感到放松。peaceful“宁静的”，在此处作定语，修饰名词atmosphere。 28．The artist walked along the ________ (小径) in the forest to find inspiration. 【答案】path 【详解】句意：这位艺术家沿着森林中的小径行走，寻找灵感。根据汉语提示可知，path“小径”，可数名词，根据“the”以及语境可知，此处特指某一条具体的小径，需用名词单数。故填path。 29．The students are discussing the ________ (重要性) of great inventions. 【答案】importance 【详解】句意：学生们正在讨论伟大发明的重要性。根据汉语提示可知，importance“重要性”，不可数名词。故填importance。 30．The ancient coins are very ________ (有价值的) for historical research. 【答案】valuable 【详解】句意：这些古钱币对于历史研究来说非常有价值。句中“very”后接形容词原级，括号内“有价值的”对应的英文单词是valuable，故填valuable。 三、完成句子(本大题共10小题，每小题4分，共40分) 31．他很小就对绘画产生了兴趣。 He ________ ________ ________ drawing at an early age. 【答案】 became/was/got interested in 【详解】原句中“对……产生兴趣”是关键词，表示“对……产生兴趣”的词组有become interested in…；be interested in…和get interested in…，根据“at an early age”可知，句子是一般过去时，动词要用过去式，become的过去式是became；主语是第三人称单数，be动词用was；get的过去式是got，故填became/was/got；interested；in。 32．a, that, important, exploration, is, the, compass, very, invention, forever, changed (.) (连词成句) ____________________________________________________________________________ 【答案】The compass is a very important invention that forever changed exploration. 【详解】根据所给标点可知应用陈述句的形式，句子为含有定语从句的复合句。分析所给单词，The compass作主句主语，意为“指南针”；is是主句谓语动词；a very important invention作主句表语，意为“一个非常重要的发明”；that引导定语从句，修饰先行词invention，在从句中作主语；forever changed是定语从句的谓语部分，意为“永远地改变了”；exploration作定语从句的宾语，意为“探索”。故填The compass is a very important invention that forever changed exploration.“指南针是一项非常重要的发明，它永远地改变了探索（的方式）。”。 33．the British scientist, by, penicillin, accident, discovered (.)（连词成句） _____________________________________________________________. 【答案】The British scientist discovered penicillin by accident 【详解】the British scientist作主语，且位于句首the首字母应大写，discovered作谓语，penicillin作宾语，by accident作状语。句子为一般过去时，描述过去发生的事，故填The British scientist discovered penicillin by accident“这位英国科学家偶然间发现了青霉素”。 34．How amazing the movie is! (变为同义句) ________ ________ amazing movie it is ! 【答案】 What an 【详解】句意：这部电影多么精彩啊！这是感叹句转换，“amazing movie”是名词短语，且amazing以元音音素开头，符合“What+an+形容词+可数名词单数+主谓”。故填What；an。 35．She is too young to understand this. (同义句) She is ________ young ________ she can’t understand this. 【答案】 so that 【详解】句意：她太小了以至于不能理解这个。too…to…表示“太……而不能……”，可与“so…that…”引导的结果状语从句进行同义转换，so后接形容词或副词，that后接从句。故填so；that。 36．He is good at inventing small things for daily life. (改为同义句) He ______ ______ ______ inventing small things for daily life. 【答案】 does well in 【详解】句意：他擅长发明日常生活的小物件。原句中“is good at”表示“擅长”，改为同义句时，可以用“do well in”来替换，因为主语“He”是第三人称单数，所以“do”要变为“does”，其他部分保持不变。故填does；well；in。 37．I happened to find this old family photo by chance while cleaning out the attic over the weekend. (保持原句意思不变) I found this old family photo ________ ________ while cleaning out the attic over the weekend. 【答案】 by accident 【详解】句意：周末打扫阁楼时，我偶然发现了这张旧家庭照片。改为同义句，根据原句的“by chance”可知，空处填与“by chance”意思相近的短语，“by chance”表达“偶然”，“by accident”也表达“偶然”。故填by；accident。 38．People used plants to make shoes around 7,000 BCE to protect their feet. (对画线部分提问) ________ ________ ________ use plants to make shoes around 7,000 BCE? 【答案】 Why did people 【详解】句意：公元前7000年左右，人们用植物制作鞋子来保护脚。画线部分表示目的，疑问句应用why提问，句首单词首字母需大写；原句时态是一般过去时，所以疑问词后接助动词did；主语people置于助动词之后。故填Why；did；people。 39．We should use social media to spread useful knowledge. (对画线部分提问) ________ ________ ________ use social media to spread? 【答案】 What should we 【详解】句意：我们应该利用社交媒体传播有用的知识。画线部分表示“传播的内容”，疑问句应用what提问，句首单词首字母需大写；原句的情态动词should在疑问句中要提到主语we之前，置于疑问词之后。故填What；should；we。 40．Newton made the discovery of gravity because he watched an apple fall.（对划线部分提问） ______ ______ Newton make the discovery of gravity? 【答案】 Why did 【详解】句意：牛顿因为看到苹果落地才发现了万有引力。划线部分是原因状语。对原因提问用Why，原句是一般过去时，需加助动词did。故填Why；did。 四、短文填空(本大题共10小题，每小题3分，共30分) Complete the passage with the given words in their proper forms. (用所给单词的适当形式完成短文，使其内容通顺。) An Unlikely Inventor Mr. Brown was a retired teacher who lived a quiet life. He had plenty of spare time, which he usually spent 41 (garden). However, an unexpected event changed his life. One day, his neighbor, an old lady, fell and broke her hip. The 42 (treat) took months, and she lost her independence. Mr. Brown felt sad. He wanted to help people like her. He started tinkering (修补) in his garage with some old pipes and 43 (tube). He had no engineering training, but he had a good idea. He wanted to create a device to help people stand up 44 (easy). He used light but strong materials he found in a scrapyard. He worked day and night. After many 45 (fail), he finally 46 (success). His invention was a simple frame that used leverage (杠杆作用) . To everyone’s surprise, it worked perfectly. It allowed elderly people to get out of chairs without help. Mr. Brown didn’t want to make a fortune. He decided to donate his design to a local charity. He believed in the values of 47 (social)—that we should help each other. He even worked as a volunteer to 48 (teacher) others how to build it. His invention won a community award. But for him, the best reward was seeing his neighbor smile again. His story shows that you don’t need to be a scientist to be an 49 (invent). You just need a caring heart and a total commitment to 50 (solve) a problem. 【答案】 41．gardening 42．treatment 43．tubes 44．easily 45．failures 46．succeeded 47．socialism 48．teach 49．inventor 50．solving 【导语】本文讲述了退休教师布朗先生成为非专业发明家的暖心故事。 41．句意：他有很多空闲时间，通常都花在园艺上。根据“spent”可知，此处使用spend time doing sth.“花费时间做某事”，所以使用动名词gardening“园艺”。 42．句意：治疗花了数月时间，她失去了自理能力。根据“took months”可知，此处使用名词作主语，treat的名词为treatment“治疗”。 43．句意：他开始在车库里用一些旧管子和软管子进行修补。根据“some old pipes and”可知，此处使用名词复数，与pipes并列，tube的复数为tubes“软管子”。 44．句意：他想创造一种设备，帮助人们轻松站立。根据“stand up”可知，此处使用副词修饰动词，easy的副词为easily“容易地”。 45．句意：经过多次失败，他终于成功了。根据“many”可知，此处使用名词复数，fail的名词为failure“失败”，其复数为failures。 46．句意：经过多次失败，他终于成功了。根据“After many failures”可知，此处指经过多次失败后，他成功了，使用动词succeed“成功”，根据语境可知，句子使用一般过去时，动词使用过去式succeeded。 47．句意：他相信社会主义价值观——我们应该互相帮助。根据“the values of”可知，此处表示社会主义价值观，使用名词，social的名词为socialism“社会主义”。 48．句意：他甚至作为一名志愿者教其他人如何建造它。根据“worked as a volunteer to”可知，此处使用动词原形表目的，teacher的动词为teach“教”。 49．句意：他的故事表明，你不需要成为一名科学家才能成为发明家。根据“an”可知，此处使用名词单数，invent的名词为inventor“发明家”。 50．句意：你只需要有一颗关爱的心，并致力于解决问题。根据“commitment to”可知，此处to是介词，需使用动名词，solve的动名词为solving“解决”。 $ 班级 姓名 学号 分数 Unit 2 Great inventions and discoveries 单元重点单词变形短语语法句型精练 （时间：60分钟，满分：100分） 单元知识点默写 一、词性转换 试卷第1页，共3页 学科网（北京）股份有限公司 1. discovery (n. 发现；发觉) → ________ (v. 发现) 2. exploration (n. 探索；勘查) → ________ (v. 探索；勘查) 3. economy (n. 经济) → ________ (adj. 经济的) 4. illness (n. 疾病，病) → ________ (adj. 生病的) 5. socialism (n. 社会主义) → ________ (adj. 社会的) 6. totally (adv. 全部地；整个地) → ________ (adj. 全部的；整个的) 7. serious (adj. 严重的；严肃的) → ________ (adv. 严重地；严肃地) 8. medical (adj. 医学的；医疗的) → ________ (n. 药；医学) 9. volunteer (v./n. 自愿做；志愿者) → ________ (adj. 志愿的；自愿的) 10. herself (pron. 她自己) → ________ (pron. 她) 二、单词拼写 1. 发现；发觉 → ________ 2. 古代的；古老的 → ________ 3. 探索；勘查 → ________ 4. 轮子；车轮 → ________ 5. 经济 → ________ 6. 材料；原料 → ________ 7. 渔网 → ________ 8. 战争 → ________ 9. （身体或精神上的）疾病，病 → ________ 10. 社会主义 → ________ 11. 习惯 → ________ 12. 几乎不；几乎没有 → ________ 13. 全部地；整个地 → ________ 14. 电话 → ________ 15. （金属、塑料、橡皮制成的）管，管子 → _______ 16. 骨头 → ________ 17. X射线；X光 → ________ 18. 颁奖；奖；奖品 → ________ 19. 爵士；（对不认识男性的尊称）先生 → _______ 20. 霉；霉菌 → ________ 21. (pl.) 细菌 → ________ 22. 救命的；救生的 → ________ 23. 进程；课程 → ________ 24. 医治；治疗 → ________ 25. 严重的；严肃的 → ________ 26. 疟疾 → ________ 27. 医学的；医疗的 → ________ 28. 自愿做；义务做；无偿做；志愿者 → ________ 29. （用作女性的反身代词）她自己，自己 → _____ 30. 空闲的 → ________ 三、短语拼写 1. 偶然；意外地 → ________ 2. 令人惊讶的是 → ________ 3. 使……变成 → ________ 4. 使……变亮 → ________ 5. 保持联系 → ________ 单元知识点习题训练 1、 用括号内所给单词的适当形式填空(本大题共20小题，每小题1分，共20分) 1．She practises ________ (draw) every day to improve her skills. 2．The teacher’s ________ (encourage) words made me feel more confident before the exam. 3．The wounded were taken to the local hospital by the ________ workers. (medicine) 4．He stopped ________ (smoke) because it was bad for his health. 5．The wheel ________ (change) the way people traveled since it was invented. 6．He would rather ________ (be) a sculptor than a painter when he grows up. 7．I’m sorry I shouted at you just now. I was just feeling ________ (stress). 8．The room was ________ (total) dark when the lights went out. 9．I can ________ (hard) believe what he said. 10．________ (social) is an important political idea in some countries. 11．He was absent from school because of ________ (ill). 12．The ________ (wheel) on the old cart are made of wood. 13．They are planning another ________ (explore) to the South Pole. 14．The ________ (discover) of the new species surprised the scientists. 15．The company is ________ considering the young inventor’s creative proposal for a new type of battery. (serious) 16．The discovery of penicillin was a major breakthrough in the ________ of many bacterial infections. (treat) 17．The new invention brought significant ________ benefits to the local community by creating many job opportunities. (economy) 18．Hope everybody can find his own ________ (strong) and make full use of it. 19．The telephone ________ (invent) by Bell; it helped people keep in touch easily. 20．The volunteers ________ (clean) the art museum when we got there. 二、根据汉语提示完成单词(本大题共10小题，每小题1分，共10分) 21．The students are learning about the ________ (历史) of Chinese art. 22．The doctor used a special tool to ________ (检查) the patient’s eyes. 23．Edison is a famous ________ (发明家) who invented the light bulb. 24．The Internet makes communication more ________ (方便的) than before. 25．This new technology has a great ________ (影响) on our daily life. 26．The little boy has a ________ (天赋) for music. 27．The painting has a ________ (宁静的) atmosphere that makes people feel relaxed. 28．The artist walked along the ________ (小径) in the forest to find inspiration. 29．The students are discussing the ________ (重要性) of great inventions. 30．The ancient coins are very ________ (有价值的) for historical research. 三、完成句子(本大题共10小题，每小题4分，共40分) 31．他很小就对绘画产生了兴趣。 He ________ ________ ________ drawing at an early age. 32．a, that, important, exploration, is, the, compass, very, invention, forever, changed (.) (连词成句) ____________________________________________________________________________ 33．the British scientist, by, penicillin, accident, discovered (.)（连词成句） _____________________________________________________________. 34．How amazing the movie is! (变为同义句) ________ ________ amazing movie it is ! 35．She is too young to understand this. (同义句) She is ________ young ________ she can’t understand this. 36．He is good at inventing small things for daily life. (改为同义句) He ______ ______ ______ inventing small things for daily life. 37．I happened to find this old family photo by chance while cleaning out the attic over the weekend. (保持原句意思不变) I found this old family photo ________ ________ while cleaning out the attic over the weekend. 38．People used plants to make shoes around 7,000 BCE to protect their feet. (对画线部分提问) ________ ________ ________ use plants to make shoes around 7,000 BCE? 39．We should use social media to spread useful knowledge. (对画线部分提问) ________ ________ ________ use social media to spread? 40．Newton made the discovery of gravity because he watched an apple fall.（对划线部分提问） ______ ______ Newton make the discovery of gravity? 四、短文填空(本大题共10小题，每小题3分，共30分) Complete the passage with the given words in their proper forms. (用所给单词的适当形式完成短文，使其内容通顺。) An Unlikely Inventor Mr. Brown was a retired teacher who lived a quiet life. He had plenty of spare time, which he usually spent 41 (garden). However, an unexpected event changed his life. One day, his neighbor, an old lady, fell and broke her hip. The 42 (treat) took months, and she lost her independence. Mr. Brown felt sad. He wanted to help people like her. He started tinkering (修补) in his garage with some old pipes and 43 (tube). He had no engineering training, but he had a good idea. He wanted to create a device to help people stand up 44 (easy). He used light but strong materials he found in a scrapyard. He worked day and night. After many 45 (fail), he finally 46 (success). His invention was a simple frame that used leverage (杠杆作用) . To everyone’s surprise, it worked perfectly. It allowed elderly people to get out of chairs without help. Mr. Brown didn’t want to make a fortune. He decided to donate his design to a local charity. He believed in the values of 47 (social)—that we should help each other. He even worked as a volunteer to 48 (teacher) others how to build it. His invention won a community award. But for him, the best reward was seeing his neighbor smile again. His story shows that you don’t need to be a scientist to be an 49 (invent). You just need a caring heart and a total commitment to 50 (solve) a problem. $