Unit 5 A fine balance 知识点总结 2026-2027学年外研版九年级英语上册

该初中英语单元复习讲义以“生态平衡与环境保护”话题为核心，按“词汇-短语-句型-语法-写作”逻辑构建知识体系。通过主题分类词汇表（含音标、搭配、例句）、短语辨析对比表、句型公式化表格及定语从句用法对比表，系统呈现知识脉络，突出定语从句等重难点的内在联系。 讲义亮点在于分层练习设计与文化渗透，基础过关20题夯实词汇语法，能力提升10题强化综合应用，写作模块提供基础版（90词）和提升版（130词）范文及框架，助力不同层次学生提升语言能力。结合《没有我们的世界》等文化常识培养环保意识，自测题附详细解析支持自主复习，教师可据此实施精准教学。

外研版（2026秋新版）九年级上册 Unit 5 A fine balance 单元知识点总结 适用教材：外研版（2026秋新版）九年级上册 | 适用学段：初三上学期 | 资料类型：单元知识点总结 课标对接 【话题】生态平衡与环境保护（Ecological balance and environmental protection） 【语言技能】能听懂并讨论关于生态系统、环境保护、生物多样性的话题；能运用定语从句（关系代词 that/which）描述事物和现象；能读懂关于生态平衡的说明文和议论文；能写一篇关于人们维持生态平衡努力的调查报告。 【文化意识】了解生态平衡与生物多样性的重要性，认识人类活动对自然环境的影响，培养环保意识和可持续发展观念。 【核心语法】定语从句(2) —— 关系代词 that/which 在从句中作主语/宾语，区分 that 和 which 的使用场景。 【文化常识】The World Without Us（《没有我们的世界》）；生态平衡与生物多样性（Ecological balance and biodiversity）。 目录 一、重点词汇（按主题分类，含音标/词性/搭配/例句） 二、重点短语与固定搭配（22个高频短语，含辨析对比） 三、重点句型（8大核心句型，含公式+课文原句+仿写范例） 四、语法精讲（定语从句(2) —— 关系代词 that/which 的用法） 五、单元话题写作（A research report on people's efforts to keep ecosystems balanced，含写作框架+范文2篇） 六、易错点与难点突破（10大高频易错，含正误对比+原因分析） 七、文化常识（The World Without Us / 生态平衡与生物多样性） 八、单元自测（基础过关20题 + 能力提升10题） 附：参考答案与详细解析 一、重点词汇（Words） 1.1 生态系统与自然环境类 英文 音标 词性 中文 用法与搭配 例句 ecosystem /ˈiːkəʊsɪstəm/ n. 生态系统 a balanced ecosystem protect the ecosystem Every living thing plays a role in the ecosystem. nature /ˈneɪtʃə/ n. 自然；自然界 in nature nature reserve We should learn to live in harmony with nature. environment /ɪnˈvaɪrənmənt/ n. 环境 protect the environment the natural environment Pollution is harmful to the environment. earth /ɜːθ/ n. 地球；大地 on earth protect the earth The earth is our only home. forest /ˈfɒrɪst/ n. 森林 rain forest forest fire Forests are important for keeping the air clean. desert /ˈdezət/ n. 沙漠 the Sahara Desert in the desert The desert is expanding because of climate change. river /ˈrɪvə/ n. 河流；江 the Yangtze River cross the river Many rivers have been polluted by factories. ocean /ˈəʊʃn/ n. 海洋 the Pacific Ocean ocean pollution The ocean is home to millions of sea animals. animal /ˈænɪml/ n. 动物 wild animals endangered animals Many animals are losing their natural homes. natural /ˈnætʃrəl/ adj. 自然的；天然的 natural resources natural world Natural disasters can destroy the balance of ecosystems. 1.2 人类活动与环境影响类 英文 音标 词性 中文 用法与搭配 例句 human /ˈhjuːmən/ n./adj. 人类；人的 human beings human activities Human activities have a great influence on nature. pollution /pəˈluːʃn/ n. 污染 air/water pollution noise pollution Air pollution is a serious problem in many cities. noise /nɔɪz/ n. 噪音；噪声 noise pollution make a noise Traffic noise is harmful to people's health. traffic /ˈtræfɪk/ n. 交通；车辆 traffic jam traffic noise Too much traffic causes air and noise pollution. tourist /ˈtʊərɪst/ n. 游客；旅游者 a tourist attraction millions of tourists Tourists sometimes damage the natural environment. activity /ækˈtɪvəti/ n. 活动 human activities outdoor activities Some human activities are destroying the ecosystem. disappear /ˌdɪsəˈpɪə/ v. 消失；灭绝 disappear from... disappear completely Many species of animals are disappearing from the earth. influence /ˈɪnfluəns/ n./v. 影响；作用 have an influence on influence sb. to do Climate change has a great influence on ecosystems. 1.3 环境保护与平衡类 英文 音标 词性 中文 用法与搭配 例句 protect /prəˈtekt/ v. 保护；防护 protect...from... protect the environment We must protect the forest from being cut down. balance /ˈbæləns/ n./v. 平衡；使平衡 a fine balance keep the balance It is important to keep a balance between humans and nature. increase /ɪnˈkriːs/ v./n. 增加；增长 increase by... a sharp increase The number of tourists has increased greatly. form /fɔːm/ v./n. 形成；形式 form a habit in the form of A new forest is forming after years of protection. allow /əˈlaʊ/ v. 允许；准许 allow sb. to do sth. be allowed to do We should not allow pollution to destroy the river. remain /rɪˈmeɪn/ v. 保持；剩余 remain balanced remain silent The ecosystem must remain balanced for all living things. drop /drɒp/ v./n. 下降；滴；落下 drop by... a drop of water The temperature in the forest has dropped sharply. fill /fɪl/ v. 充满；填满 fill...with... be filled with The river is filled with pollution from the factory. depend /dɪˈpend/ v. 依靠；取决于 depend on/upon It depends. All animals depend on the ecosystem for survival. replace /rɪˈpleɪs/ v. 取代；替换 replace A with B be replaced by We should replace plastic bags with cloth ones. material /məˈtɪəriəl/ n./adj. 材料；物质的 natural materials building materials Using natural materials can help protect the environment. imagine /ɪˈmædʒɪn/ v. 想象；设想 imagine doing sth. imagine that... Can you imagine a world without animals? 二、重点短语与固定搭配（Phrases） 2.1 课文核心短语 短语 中文释义 课文原句/语境 用法提示 a fine balance 一个微妙的平衡 Nature keeps a fine balance. fine 在此表"微妙的/精细的"，不表"好的"。 keep the balance 保持平衡 It is important to keep the balance of nature. keep the balance = 保持平衡，也可用 maintain the balance。 protect...from... 保护...免受... We must protect the forest from being destroyed. protect...from... 后接名词或动名词。 depend on/upon 依靠；取决于 All living things depend on the ecosystem. depend on = 依靠；It depends. = 看情况而定。 have an influence on 对...有影响 Human activities have a great influence on nature. have an influence on = have an effect on。 disappear from... 从...消失 Many animals are disappearing from the earth. disappear from + 地点，动词 disappear 的名词形式为 disappearance。 be filled with 充满；装满 The river is filled with pollution. be filled with = be full of，两者可互换。 replace A with B 用B替换A We should replace plastic bags with cloth ones. replace A with B = 用B代替A，被动：A is replaced by B。 allow sb. to do sth. 允许某人做某事 The law does not allow factories to pollute rivers. allow sb. to do sth.，被动：sb. be allowed to do sth. in the form of 以...的形式 Pollution comes in the form of smoke and waste. in the form of + 名词，表"以某种形式"。 increase by 增加了（幅度） The number of tourists increased by 30%. increase by + 百分比/数量，表增长的幅度。 increase to 增加到（结果） The population increased to 10 million. increase to + 最终数字，表增长后达到的结果。 drop by 下降了（幅度） The temperature dropped by 5 degrees. drop by + 数量，表下降的幅度。 remain balanced 保持平衡 The ecosystem must remain balanced. remain + 形容词，表"保持某种状态"。 fill...with... 用...填满... They filled the land with trees. fill A with B = 用B填满A，被动：A is filled with B。 form a habit 形成习惯 We should form the habit of protecting the environment. form a habit of doing sth. = 养成做某事的习惯。 imagine doing sth. 想象做某事 Can you imagine living without water? imagine + doing，不接 to do。 a sharp increase 急剧增长 There has been a sharp increase in pollution. a sharp increase/drop = 急剧增长/下降，sharp 修饰变化。 noise pollution 噪音污染 Traffic is a major cause of noise pollution. noise pollution 是固定搭配，不可数。 natural resources 自然资源 We should use natural resources wisely. natural resources 常用复数，表"自然资源"。 human activities 人类活动 Human activities are changing the climate. human activities 常用复数形式。 in harmony with 与...和谐相处 We should live in harmony with nature. in harmony with + 名词，表"与...和谐" 2.2 短语辨析 短语A 短语B 区别 例句 increase by increase to increase by 后接增长幅度； increase to 后接增长后的最终结果 The number increased by 20%. The number increased to 120. drop by drop to drop by 后接下降幅度； drop to 后接下降后的最终结果 The temperature dropped by 5 degrees. The temperature dropped to zero. protect...from... prevent...from... protect...from... = 保护...免受（防御性）； prevent...from... = 阻止...做（阻止性） We protect forests from fire. We prevent people from cutting trees. have an influence on have an effect on 两者含义基本相同，都表"对...有影响"； influence 侧重潜移默化的影响，effect 侧重产生的效果 TV has an influence on children. The medicine had a good effect on him. be filled with be full of 两者含义相同，可互换； be filled with 强调"被装满"的动作结果； be full of 强调"充满"的状态 The bottle is filled with water. The bottle is full of water. 三、重点句型（Sentence Patterns） 3.1 八大核心句型 编号 句型 功能 公式 / 课文原句 / 仿写 1 It is + adj. + to do sth. 表达"做某事是...的" 公式：It is + adj. + (for sb.) + to do sth. 课文：It is important to keep the balance of nature. 仿写：It is necessary to protect the environment. 2 S + that/which + V + ...（定语从句——作主语） 用定语从句修饰名词 公式：先行词 + that/which + 谓语 + 其余 课文：The river that flows through the city is polluted. 仿写：The forest which provides us with fresh air is in danger. 3 S + that/which + S + V + ...（定语从句——作宾语） 用定语从句修饰名词 公式：先行词 + that/which + 主语 + 谓语 + 其余 课文：The pollution that we see in the river is very serious. 仿写：The animals that we protect are part of the ecosystem. 4 S + allow + sb. + to do sth. 表达"允许某人做某事" 公式：主语 + allow + sb. + to do sth. 课文：The law does not allow factories to pollute rivers. 仿写：The government does not allow people to hunt wild animals. 5 S + depend on + sth./sb. 表达"依靠/取决于" 公式：主语 + depend on + 名词/代词/动名词 课文：All living things depend on the ecosystem. 仿写：Whether we succeed depends on our efforts. 6 S + protect + A + from + B 表达"保护A免受B" 公式：主语 + protect + 名词/代词 + from + 名词/动名词 课文：We must protect the forest from being cut down. 仿写：Trees protect the soil from being washed away. 7 S + fill + A + with + B 表达"用B填满A" 公式：主语 + fill + A + with + B 课文：They filled the land with trees. 仿写：Pollution has filled the river with waste. 8 S + have + a great influence on + sth. 表达"对...有很大影响" 公式：主语 + have + a/an + adj. + influence on + 名词 课文：Human activities have a great influence on nature. 仿写：Technology has a great influence on our daily life. 3.2 同义句转换 原句 同义句 知识点 The river is filled with pollution. The river is full of pollution. be filled with = be full of，可互换。 Human activities have an influence on nature. Human activities have an effect on nature. have an influence on = have an effect on。 We must protect the forest from destruction. We must prevent the forest from being destroyed. protect...from... 与 prevent...from... 在此语境下可互换。 We should replace plastic with cloth. Plastic should be replaced by cloth. replace A with B 的被动形式为 A is replaced by B。 All animals depend on the ecosystem for survival. The survival of all animals depends on the ecosystem. depend on 的主语不同，句式不同但含义相同。 四、语法精讲（Grammar） 4.1 定语从句概述 【中考考频】定语从句是中考重点语法项目，常出现在单项选择、完形填空和阅读理解中。本单元重点考查关系代词 that 和 which 在定语从句中作主语和宾语的用法，以及两者的区别。 定语从句（Attributive Clause）是在复合句中修饰名词或代词的从句。被修饰的名词或代词称为"先行词"（Antecedent），连接先行词和定语从句的词称为"关系代词"（Relative Pronoun）。 核心公式：先行词 + 关系代词 that/which + 从句其余部分。 4.2 关系代词 that/which 作主语 用法：当关系代词在定语从句中作主语时，从句的谓语动词与先行词在人称和数上保持一致。 公式：先行词(物) + that/which + 谓语动词 + 其余 例句：The river that flows through the city is polluted.（那条流经城市的河被污染了。） 例句：The forest which provides us with fresh air is in danger.（那片为我们提供新鲜空气的森林正处于危险之中。） 例句：Pollution that comes from factories is very harmful.（来自工厂的污染非常有害。） 注意：作主语时 that 和 which 一般可以互换，但 that 使用更广泛。 4.3 关系代词 that/which 作宾语 用法：当关系代词在定语从句中作宾语时，that/which 可以省略。 公式：先行词(物) + that/which + 主语 + 谓语 + 其余 例句：The pollution that we see in the river is serious.（我们在河里看到的污染很严重。） 例句：The animals which we protect are part of the ecosystem.（我们保护的动物是生态系统的一部分。） 例句：The book that I read yesterday is about the environment.（我昨天读的那本书是关于环境的。） 注意：作宾语时 that 和 which 一般可以互换，且都可以省略。 4.4 只能用 that 的情况 在以下情况中，关系代词只能用 that，不能用 which： 1. 先行词被形容词最高级修饰时： This is the most beautiful forest that I have ever seen.（这是我见过的最美的森林。） 2. 先行词被序数词修饰时： The first river that they cleaned is now very clean.（他们清理的第一条河现在非常干净。） 3. 先行词被 all, every, any, no, the only, the very 等修饰时： All the pollution that comes from factories should be controlled.（所有来自工厂的污染都应该被控制。） 4. 先行词中既有人又有物时： We talked about the people and the animals that live in the forest.（我们讨论了生活在森林里的人和动物。） 5. 先行词为不定代词（something, anything, nothing, everything 等）时： Is there anything that we can do to protect the environment?（我们能做些什么来保护环境吗？） 4.5 只能用 which 的情况 在以下情况中，关系代词只能用 which，不能用 that： 1. 引导非限制性定语从句时（从句前有逗号）： The Yangtze River, which is the longest river in China, is home to many animals.（长江是中国最长的河流，是许多动物的家园。） 2. 介词后作宾语时： This is the forest in which many rare animals live.（这就是许多珍稀动物生活的森林。） 3. 先行词本身是 that 时： That which is harmful to the environment should be stopped.（对环境有害的东西应该被制止。） 4.6 that/which 综合对比表 使用场景 that which 例句 作主语（一般情况） 可以 可以 The river that/which flows through the city is polluted. 作宾语（一般情况） 可以（可省略） 可以（可省略） The pollution that/which we see is serious. 先行词被最高级修饰 必须 不可 This is the most beautiful forest that I have seen. 先行词被 all/every/any 等修饰 必须 不可 All the animals that live here need protection. 先行词中既有人又有物 必须 不可 The people and animals that live in the forest. 非限制性定语从句 不可 必须 The river, which is very long, is polluted. 介词后作宾语 不可 必须 The forest in which they live is beautiful. 4.7 定语从句常见错误警示 1. 从句中谓语动词重复宾语： 错误：The pollution that we see it is serious.（it 多余） 正确：The pollution that we see is serious. 2. 关系代词与先行词不一致： 错误：The people which live in the village are farmers.（指人应用 who/that） 正确：The people who/that live in the village are farmers. 3. 非限制性定语从句误用 that： 错误：The river, that is very long, is polluted.（非限制性定语从句不能用 that） 正确：The river, which is very long, is polluted. 五、单元话题写作（Writing） 5.1 写作任务：A research report on people's efforts to keep ecosystems balanced 本单元写作任务是以"A research report on people's efforts to keep ecosystems balanced"（关于人们维持生态系统平衡的努力的调查报告）为主题，写一篇调查报告。可以介绍你调查的生态系统、人们为保护该生态系统所做的努力、存在的问题以及你的建议。要求：80-120词，结构清晰，语言通顺，可适当使用定语从句 that/which 丰富表达。 5.2 写作框架 段落 内容 可用句型 示例 第一段 引出话题：介绍调查对象及背景 I did a research on... The ecosystem that I studied is... ...is a fine balance of... I did a research on the forest ecosystem near our city. The forest, which is home to many animals, is facing serious problems. 第二段 主体内容：描述人们的努力与存在的问题 People have made efforts to... They protect...from... However, there are still problems that... Local people have made great efforts to protect the forest. They have planted trees to replace the ones that were cut down. However, pollution that comes from nearby factories still harms the ecosystem. 第三段 总结建议：提出改进建议与展望 In my opinion, we should... It is important to... I believe that...will... In my opinion, we should do more to keep the balance of nature. I believe that the ecosystem will remain balanced if we all work together. 5.3 范文 【范文一】基础版（约90词）—— A research report on the forest ecosystem I did a research on the forest ecosystem near our town. The forest, which is home to many wild animals, is very important for the environment. Local people have made efforts to protect the forest. They have formed a group that plants trees every spring. They also prevent people from cutting down trees. The forest provides us with fresh air that we all need to live. However, there are still problems. Pollution from factories is harming the river that flows through the forest. In my opinion, the government should make stricter laws. I believe that our efforts will help keep the ecosystem balanced. 【范文二】提升版（约130词）—— A survey on ocean protection efforts I conducted a survey on people's efforts to protect the ocean ecosystem. The ocean, which covers over 70% of the earth's surface, is a fine balance of living things. Many organisations have made great efforts to protect the ocean. They have started programmes that clean up plastic waste from the sea. Scientists are studying the animals that depend on the ocean for survival. Some countries have passed laws that do not allow factories to dump waste into the ocean. These efforts have had a positive influence on the ocean environment. However, the ocean is still being polluted. Every year, millions of tons of plastic enter the ocean. In my opinion, we should replace plastic bags with cloth ones and reduce the waste that we produce. We all have a role to play in protecting the ocean. If we work together, the ocean ecosystem will remain balanced for future generations. 5.4 写作好词好句积累 类别 表达 适用场景 引出话题 I did a research on... The ecosystem that I studied is... ...is a fine balance of... 开头介绍调查对象 描述生态系统 The forest, which is home to..., is... The river that flows through... The animals that depend on... 用定语从句描述生态系统 描述保护努力 People have made efforts to... They have formed a group that... They protect...from... 描述人们为保护生态所做的努力 提出问题 However, there are still problems that... Pollution from...is harming... ...is still being polluted. 指出存在的问题 提出建议 In my opinion, we should... It is important to... I believe that...will... 结尾表达建议与展望 六、易错点与难点突破（Common Mistakes） 编号 易错点 错误示例 正确写法 原因分析 1 定语从句中重复宾语 x The pollution that we see it is serious. v The pollution that we see is serious. 关系代词 that/which 已在从句中作宾语，不能再加 it。 2 非限制性定语从句误用 that x The river, that is very long, is polluted. v The river, which is very long, is polluted. 非限制性定语从句（有逗号）只能用 which，不能用 that。 3 最高级后误用 which x This is the most beautiful forest which I have seen. v This is the most beautiful forest that I have seen. 先行词被最高级修饰时，只能用 that。 4 increase by 与 increase to 混淆 x The number increased to 20%. v The number increased by 20%. increase by 接增长幅度（百分比）；increase to 接增长后的最终数字。 5 protect...from 后接动词不定式 x Trees protect the soil from wash away. v Trees protect the soil from being washed away. protect...from 后接名词或动名词，不接动词原形。 6 allow 后漏 to x The law allows factories pollute rivers. v The law allows factories to pollute rivers. allow sb. to do sth. 中 to 不可省略。 7 depend on 中 on 误用 x All animals depend in the ecosystem. v All animals depend on the ecosystem. depend on/upon 是固定搭配，介词用 on 不用 in。 8 fill...with 与 be filled with 混淆 x The river fill with pollution. v The river is filled with pollution. fill...with... 是主动形式（主语是人）；be filled with 是被动形式（主语是物）。 9 imagine 后接不定式 x Can you imagine to live without water? v Can you imagine living without water? imagine 后接动名词，不接动词不定式。 10 remain 后接副词 x The ecosystem must remain balancedly. v The ecosystem must remain balanced. remain 是系动词，后接形容词作表语，不接副词。 七、文化常识（Culture Link） 7.1 《没有我们的世界》（The World Without Us） 《没有我们的世界》（The World Without Us）是美国作家 Alan Weisman 于2007年出版的一本畅销书。该书探讨了一个引人深思的假设：如果人类突然从地球上消失，自然界会发生什么变化？ 书中描绘了一个惊人的画面：没有人类的世界中，生态系统（ecosystem）将逐渐恢复平衡（balance）。城市会被森林（forest）覆盖，河流（river）会变得清澈，野生动物（animal）会重新占领曾经属于它们的领地。大自然（nature）有着惊人的自我修复能力，但这需要时间。 这本书提醒我们：人类活动（human activities）对地球环境（environment）的影响是巨大的。我们不是地球的主人，而是生态系统的一部分。只有保持生态平衡（keep the balance of nature），人类才能与自然和谐共处（live in harmony with nature）。 7.2 生态平衡与生物多样性（Ecological balance and biodiversity） 生态平衡（ecological balance）是指在一个生态系统中，各种生物的数量和比例保持相对稳定的状态。每一个物种都在生态系统中扮演着独特的角色。蜜蜂传播花粉，森林净化空气，河流提供水源——这一切构成了一幅精妙的平衡（a fine balance）画面。 生物多样性（biodiversity）是指地球上生物种类的丰富程度。地球上约有870万种物种，但其中许多正面临灭绝的威胁。科学家估计，每年约有27,000种物种从地球上消失（disappear from the earth）。保护生物多样性，就是保护我们赖以生存的地球（earth）。 世界各国都在采取措施保护生态环境。例如，中国建立了数千个自然保护区（nature reserves），实施了退耕还林（returning farmland to forest）政策。许多国家签署了《巴黎协定》（Paris Agreement），承诺减少碳排放，保护地球的生态平衡。 7.3 关于自然与环保的名言 名言（英文） 名言（中文） 作者 In nature, nothing exists alone. 在自然界中，没有任何事物是孤立存在的。 Rachel Carson（蕾切尔·卡森） The earth does not belong to us. We belong to the earth. 地球不属于我们，我们属于地球。 Chief Seattle（西雅图酋长） We do not inherit the earth from our ancestors; we borrow it from our children. 我们不是从祖先那里继承了地球，而是从子孙那里借来的。 Native American Proverb Look deep into nature, and then you will understand everything better. 深入观察自然，你就会更好地理解一切。 Albert Einstein（爱因斯坦） 7.4 生态环保相关英文表达 中文含义 英文表达 例句 生态平衡 ecological balance Ecological balance is important for the health of our planet. 生物多样性 biodiversity The rainforest is rich in biodiversity. 自然保护区 nature reserve The forest has become a nature reserve. 濒危物种 endangered species Pandas are an endangered species. 可持续发展 sustainable development Sustainable development meets the needs of today without harming the future. 碳足迹 carbon footprint We can reduce our carbon footprint by walking instead of driving. 全球变暖 global warming Global warming is causing ice to melt at the poles. 八、单元自测（Self-check） （本部分为"学生版"，不含答案。参考答案与解析见附录。） 第一部分：基础过关（20题） 一、根据首字母或汉语提示写出单词（10分） 1. Every living thing plays a role in the e______（生态系统）. 2. We should learn to live in harmony with n______（自然）. 3. P______（污染）is harmful to the environment. 4. The d______（沙漠）is expanding because of climate change. 5. Many animals are d______（消失）from the earth. 6. The o______（海洋）is home to millions of sea animals. 7. We must p______（保护）the forest from being cut down. 8. Human activities have a great i______（影响）on nature. 9. All animals d______（依赖）on the ecosystem for survival. 10. We should r______（替换）plastic bags with cloth ones. 二、用所给词的适当形式填空（5分，注意定语从句中关系代词的用法） 11. The river ______ (that/flow) through the city is very polluted. 12. The pollution ______ (which/we/see) in the lake is very serious. 13. This is the most beautiful forest ______ (that/I/ever/visit). 14. The animals ______ (that/live) in the forest need our protection. 15. All the trees ______ (that/plant) last year are growing well. 三、选词填空（5分） （protect...from / depend on / allow...to / fill...with / replace...with） 16. Trees ______ the soil ______ being washed away by rain. 17. Whether we succeed or not ______ ______ our efforts. 18. The government does not ______ people ______ hunt wild animals. 19. Pollution has ______ the river ______ waste from factories. 20. We should ______ plastic bags ______ cloth bags. 第二部分：能力提升（10题） 四、单项选择（5分） 21. The river ______ flows through the city is very polluted. A. who B. what C. which D. where 22. This is the most beautiful forest ______ I have ever seen. A. which B. that C. who D. what 23. The Yangtze River, ______ is the longest river in China, is home to many animals. A. that B. which C. who D. where 24. All the pollution ______ comes from factories should be controlled. A. which B. who C. that D. what 25. Which of the following sentences is CORRECT? A. The river, that is very long, is polluted. B. This is the most beautiful forest which I have seen. C. The pollution that we see in the river is serious. D. The animals which lives in the forest need protection. 五、句型转换（5分） 26. The river is polluted. It flows through the city.（合并为含定语从句的句子） The river ______ ______ through the city is polluted. 27. The pollution is serious. We see it in the river.（合并为含定语从句的句子） The pollution ______ ______ ______ in the river is serious. 28. The river is filled with pollution.（改为同义句，用 full） The river ______ ______ ______ pollution. 29. The government allows factories to dump waste into the river.（改为否定句） The government ______ ______ factories to dump waste into the river. 30. The number of tourists increased by 30% last year.（对划线部分提问，对 30% 提问） ______ ______ did the number of tourists increase by last year? 附录：参考答案与详细解析 （本部分为"教师版"，供教师批改和讲解使用。） 基础过关答案 题号 答案 解析 1 ecosystem 生态系统，注意拼写 e-co-sys-tem。 2 nature in harmony with nature 与自然和谐相处，nature 是不可数名词。 3 Pollution Pollution 污染，作主语时首字母大写，不可数名词。 4 desert desert 沙漠，注意与 dessert（甜点）区分（desert 一个 s，dessert 两个 s）。 5 disappearing are disappearing 用现在进行时，表示"正在消失"。 6 ocean the ocean 海洋，注意拼写 o-cean。 7 protect protect...from... 保护...免受...，动词原形接在情态动词 must 后。 8 influence have a great influence on 对...有很大影响，influence 是名词。 9 depend depend on 是固定搭配，主语是复数 animals，用动词原形 depend。 10 replace replace A with B 用B替换A，接在情态动词 should 后用动词原形。 11 that flows 定语从句，that 在从句中作主语，指代 the river，谓语用第三人称单数 flows。 12 which we see 定语从句，which 在从句中作宾语，从句语序为"主语 + 谓语"。 13 that I have ever visited 先行词被最高级 most beautiful 修饰，只能用 that，不能用 which。 14 that live 定语从句，that 指代 animals，复数，谓语动词用 live。 15 that were planted 定语从句，that 指代 trees，被动语态，用 were planted。 16 protect; from protect...from... 保护...免受... 17 depends on depend on 依靠，主语 Whether we succeed or not 是单数概念，用 depends。 18 allow; to allow sb. to do sth. 允许某人做某事，to 不可省略。 19 filled; with fill...with... 用...填满...，现在完成时 has filled。 20 replace; with replace A with B 用B替换A，should 后接动词原形。 能力提升答案 题号 答案 解析 21 C. which 定语从句修饰物 the river，关系代词在从句中作主语，用 which/that 均可。A who 指人；B what 不能引导定语从句；D where 是关系副词。 22 B. that 先行词被最高级 most beautiful 修饰，只能用 that，不能用 which。 23 B. which 非限制性定语从句（有逗号），只能用 which，不能用 that。 24 C. that 先行词被 all 修饰，只能用 that，不能用 which。 25 C A 错在非限制性定语从句不能用 that；B 错在最高级后不能用 which；D 错在 lives 与复数 animals 不一致（应为 live）；C 正确：that 作宾语，从句语序正确。 26 that/which flows 合并为定语从句，关系代词作主语，指代 the river。 27 that/which we see 合并为定语从句，关系代词作宾语，从句语序为"主语 + 谓语"。 28 is full of be filled with = be full of，两者含义相同可互换。 29 does not allow 一般现在时的否定句，主语 the government 是第三人称单数，用 does not allow。 30 How much 对百分比提问用 How much，也可用 What percentage。对增长的幅度提问，用 How much...by。 学科网（北京）股份有限公司 $