Unit 5 Revealing nature（知识清单）英语外研版选择性必修第一册

该高中英语单元复习知识清单围绕“Revealing nature”主题，涵盖主题理解、语篇复盘、语言运用、语法建构及输出迁移五大目标，构建了主题语篇梳理、词汇词块积累、语法句型掌握、写作任务实践的递进式学习支架。 清单通过分类呈现知识体系，如核心词汇分重点识记与阅读认知，词形变化、词块、句型系统归纳，结合主题例句与对点训练强化语言能力。特色设计“核心语法精讲”含固定结构与易错提醒，“写作清单”提供框架与素材，培养思维品质，助力学生自主复习，教师可据此精准教学。

Unit 5 Revealing nature 单元复习知识清单（学生版） 复习目标 主题目标：主题理解：用观察、证据和推理解释自然现象，理解适应、进化与生态联系。 语篇目标：语篇复盘：梳理 A Journey of Discovery 的发现过程，以及 The Secret Language of Plants 的说明结构。 语言目标：语言运用：掌握本单元核心词汇、词块与重点句式，并能在新语境中准确迁移。 语法目标：语法建构：掌握过去完成时 had done / had been done，判断过去动作的先后关系。 输出目标：表达迁移：能按日期或阶段写一篇结构清楚、语言准确的观察日志。 主题与语篇 主题：探索自然、尊重证据、理解生命适应与生态联系。 语篇1 A Journey of Discovery：达尔文在小猎犬号航行中由观察、提问到提出________观点。 语篇2 The Secret Language of Plants：用举例和类比说明植物通过________、声音和真菌网络交流。 重点识记词汇 ________ 种子；________ 遥远的；________ 样本；________ 进化；________ 猜想；________ 祖先；________ 产生；________ 特征；________ 减少；________ 责怪/归咎于；________ 原始的；________ 发现；________ 根；________ 联系/连接；________ 厘米 阅读认知词汇 disgrace 耻辱；geologist 地质学家；finch 雀科鸣禽；beak 鸟喙；evolution 进化论；tortoise 陆龟；mangrove 红树；iguana 鬣蜥；spine 刺；myth 神话；legend 传说；wasp 黄蜂；pesticide 农药；chilli 辣椒；fungus/fungi 真菌；fungal 真菌的；cybercrime 网络犯罪 词形变化 distant → ________；geologist → ________；evolve → ________；generate → ________ / generator；detect → ________ / detective；fungus（复数 ________）→ fungal 核心词块 answer the call 响应号召；in question 正在讨论的；come to ________ 形成；be similar ________ 与……相似；adapt ________ 适应；a variety ________ 多种多样的；be home ________ 是……的家园；be native ________ 原产于；tiny amounts ________ 微量的；drive ... ________ 赶走；speaking ________ 说到 重点句型 It was ... ________ ...（强调句）；It was not ... ________ ...（直到……才……）；It appears ________ ...（看来……）；so ________ ...（以便……）；While A ..., B ...（对比）；the ways ________ which ...（……的方式） 核心语法 过去完成时：________ + done；被动式 ________；表示过去某一时刻或动作之前已经发生或持续的动作。 写作任务 写观察日志：用________或阶段组织内容，记录条件、________和结果，并加入简洁感受或推断。 一、核心词汇精讲 1. suspect v. 猜想；怀疑 【用法归纳】suspect ________ ... 怀疑/猜想……；suspect sb ________ (doing) sth 怀疑某人做某事。suspect 常表示认为某事很可能属实，doubt 强调不确定或不相信。 【主题例句】Darwin suspected that the finches had evolved from a common ancestor. 【对点训练】Researchers suspected the change ________ being connected with the food available. 2. adapt v. 适应；改编 【用法归纳】adapt ________ sth 适应；adapt oneself ________ sth 使自己适应；be adapted ________ ... 改编自……；________ n. 适应/改编。 【主题例句】Species survive by adapting to changes in their environment. 【对点训练】The documentary is adapted ________ a book about island wildlife. 3. generate v. 产生；创造 【用法归纳】generate electricity/heat/ideas 产生电/热/想法；________ n. 产生；一代人；________ n. 发电机。 【主题例句】Careful observation can generate new questions as well as answers. 【对点训练】The discovery has ________ (generate) worldwide interest. 4. characteristic n. 特征；adj. 典型的 【用法归纳】a characteristic ________ ... ……的特征；be characteristic ________ ... 是……所特有的。作可数名词时常用复数 ________。 【主题例句】Different beaks are a characteristic of the finches on different islands. 【对点训练】Patience is characteristic ________ careful field researchers. 5. decline v./n. 减少；下降；谢绝 【用法归纳】decline ________ + 幅度；decline ________ + 数值；decline ________ do sth 谢绝做某事；a decline ________ ... ……的下降。 【主题例句】The tortoise population declined after goats were brought to the island. 【对点训练】The number declined ________ 15%, from 2,000 to 1,700. 6. blame v./n. 责怪；归咎于 【用法归纳】blame sb ________ sth；blame sth ________ sb；be ________ blame for ... 应对……负责；take the blame ________ ... 承担责任。 【主题例句】Human activity is often blamed for the loss of island species. 【对点训练】No single person is ________ (blame) for the failed experiment. 7. detect v. 发现；察觉 【用法归纳】detect a change/signal 发现变化/信号；________ n. 发现；________ n. 侦探。detect 强调发现不易察觉的事物。 【主题例句】Sensitive equipment can detect tiny sounds made by plant roots. 【对点训练】Early ________ (detect) of the disease can protect the whole forest. 8. link v./n. 联系；连接 【用法归纳】link A ________/________ B；be linked ________/________ ...；a link ________ A and B。 【主题例句】In a forest, plants may be linked underground by a fungal network. 【对点训练】Scientists found a close link ________ rainfall and seed production. 二、核心语法精讲：过去完成时 基本形式 肯定：________；否定：________；疑问：________ + 主语 + done?；被动：________。 核心意义 以过去某个时间或动作为参照，表示在此之前已经完成或已经持续的动作，即“________的________”。 常见标志 ________/before + 过去时间；by the time + ________；when/before/after 引导的过去时间从句。 固定结构 Hardly/Scarcely had sb done ________ ...；No sooner had sb done ________ ...；It was the first/second time that sb ________ done。 易错提醒 若 before/after 已清楚表明先后，较早动作有时可用________代替过去完成时；使用过去完成时需有明确的过去________。 1. By the end of the voyage, Darwin ________ (collect) many samples. 2. When the researchers arrived, the birds ________ (leave) the island. 3. The rare plant ________ already ________ (detect) before the report was published. 4. Hardly ________ the rain stopped when insects began to appear. 5. It was the first time that the students ________ (record) the complete growth cycle. 三、单元写作清单：观察日志 1. 话题分析 观察日志以真实观察为基础，重点写清时间、条件、显著变化和结果。可以按日期分条，也可以按生长阶段分段；语言应客观、准确，末尾可加入简短感受或推断。 2. 写作框架 开头：交代观察对象、起始时间和初始条件。 主体：按时间顺序记录可见变化，并用数据、颜色、形状或行为支持描述。 结尾：总结结果，写出感受、问题或下一步观察计划。 3. 写作素材 顺序：at first, a few days later, gradually, over the following week, by the end of ...； 变化：sprout, soften, take root, grow upwards, reach ... cm, develop leaves, produce a bud, bloom； 表达：It took ... days for ... to ...；With time going by, ...；By ..., ... had ...；What surprised me most was ... 4. 仿写任务与自检 仿写任务：选择一种常见植物或小动物，按 3-4 个日期/阶段写一篇 120-150 词的观察日志。 自检：□ 时间线清楚 □ 至少2处具体变化 □ 时态一致 □ 使用本单元词汇 □ 有简短感受/推断 ________________________________________________________________________________ ________________________________________________________________________________ ________________________________________________________________________________ ________________________________________________________________________________ ________________________________________________________________________________ ________________________________________________________________________________ 易错点01 一般过去时与过去完成时 【错因辨析】先找过去参照点，再判断哪个动作更早。不能因为句子谈过去就机械使用 had done。 【对点训练】When the scientist opened the box, the insect ________ (escape). 易错点02 be to blame 的形式 【错因辨析】be to blame 表示“应负责任”，主动形式含被动意义；不能写成 be to be blamed。 【对点训练】Human carelessness was ________ (blame) for the fire. 易错点03 decline 的搭配 【错因辨析】decline by 后接幅度，decline to 后接最终数值；表示“谢绝做某事”用 decline to do。 【对点训练】The population declined ________ 900 ________ 650 in two years. 易错点04 adapt 与介词 【错因辨析】adapt to 表示适应；be adapted from 表示改编自；be adapted for 表示为某用途改编/改造。 【对点训练】Animals must adapt ________ seasonal changes to survive. 建议用时：30分钟　满分：45分 一、默写重点单词（每题1分，共8分） 1. __________ n. 样本 2. __________ v. 进化 3. __________ v. 猜想；怀疑；觉得 4. __________ n. 祖先；原种 5. __________ v. 产生；创造 6. __________ n. 特征；特性 7. __________ v. 发现；察觉 8. __________ v. 把……联系起来；连接 二、词汇与短语运用（每题1分，共6分） 9. The researchers collected several rock ________ (sample) during the journey. 10. A species may disappear if it cannot adapt ________ rapid environmental change. 11. Her careful notes helped ________ (generate) a new question about seed growth. 12. The number of wild goats declined ________ 1,200 to 800 in five years. 13. No single factor is ________ (blame) for the sudden change. 14. New evidence links the decline ________ the loss of wetland plants. 三、重点句型与语法（每题1分，共6分） 15. By the time the ship returned, Darwin ________ (collect) a large number of samples. 16. When Darwin reached the islands, he found that the finches ________ (develop) different beaks. 17. It was not until 1859 ________ Darwin's book was published. 18. Hardly ________ the rain ________ (stop) when the frogs began to call. 19. No sooner ________ the students set up the camera than a fox appeared. 20. The team completed the fieldwork. Then they compared the samples.（用过去完成时合并） 四、写作微任务（共5分） 21. 根据以下观察记录写一段约80词的向日葵观察日志：Day 1，播下5粒种子；Day 4，3粒发芽；Day 10，茎约8厘米并长出两片叶；Day 24，出现第一个花蕾。要求时间顺序清楚，至少使用1处过去完成时。 ________________________________________________________________________________ ________________________________________________________________________________ ________________________________________________________________________________ ________________________________________________________________________________ 五、阅读理解（每题4分，共20分） Each spring, rain fills shallow hollows in a woodland near Hangzhou, creating temporary pools that vanish by midsummer. For years, hikers treated them as muddy puddles. In 2024, students from a nearby school noticed strings of frog eggs in one pool and asked why frogs chose water that would soon disappear. Under the guidance of a biologist, the group mapped twelve pools, recorded water temperature and depth each week, and installed small cameras. They did not handle the animals. Instead, they photographed the same one-metre areas and used one counting method on every visit. At first, they assumed the deepest pools would support the most young frogs. Early data seemed to agree: those pools held water longer and contained more tadpoles. Then the camera recordings changed the story. Fish had entered two of the deepest pools after a stream overflowed. Wherever fish appeared, tadpole numbers dropped sharply. The finding revealed a trade-off. Temporary pools do not offer permanent security; their value lies in a brief window. If the water disappears too early, tadpoles cannot complete their change into frogs. If it lasts too long and connects with a stream, predators may arrive. The most successful pools were not the deepest but those that held water long enough while remaining separate. This did not mean the shallowest pools were always best: three dried during an unusually hot week and lost nearly all their tadpoles. The students repeated the observations the following spring before drawing a conclusion, and the pattern returned. Instead of 'fixing' the pools by digging them deeper, the school worked with park managers to protect a variety of depths and the natural routes followed by rainwater. Fallen leaves were left at the edges because they shaded the water and supported tiny organisms that tadpoles ate. New signs now ask visitors to avoid trampling the pools during the breeding season. The project changed how the students saw ordinary places: a short-lived puddle was not an unfinished pond but a habitat shaped by timing. Nature's clues had been present all along; careful measurement revealed what a quick look had missed. 22. What first led the students to investigate the temporary pools? A. Fish were seen leaving a stream. B. Frog eggs were found in a pool that would soon vanish. C. Park managers planned to deepen the pools. D. Hikers reported that the woodland was flooding. 23. Which evidence made the students revise their first assumption? A. Deep pools changed temperature more slowly. B. Fish entered deep pools and tadpole numbers there fell. C. Shallow pools received less rain than expected. D. Cameras showed hikers walking near the pools. 24. What does the phrase 'a brief window' in Paragraph 3 refer to? A. A place where students could watch the animals. B. A season when every pool stayed completely safe. C. A limited period when water lasted long enough but predators stayed away. D. A short break between two weekly research visits. 25. Why did the students repeat the observations the following spring? A. To check whether the pattern was reliable beyond one season. B. To find a safer way to handle the tadpoles. C. To compare their results with hikers' photographs. D. To prove that the deepest pool was the most useful. 26. Which title best expresses the main idea of the passage? A. How to Build a Permanent Woodland Pond B. Why Fish Are Disappearing from City Streams C. A School Camera Project That Failed D. When a Temporary Puddle Becomes a Nursery 学科网（北京）股份有限公司1 / 10 学科网（北京）股份有限公司 $ Unit 5 Revealing nature 单元复习知识清单（教师版） 复习目标 主题目标：主题理解：用观察、证据和推理解释自然现象，理解适应、进化与生态联系。 语篇目标：语篇复盘：梳理 A Journey of Discovery 的发现过程，以及 The Secret Language of Plants 的说明结构。 语言目标：语言运用：掌握本单元核心词汇、词块与重点句式，并能在新语境中准确迁移。 语法目标：语法建构：掌握过去完成时 had done / had been done，判断过去动作的先后关系。 输出目标：表达迁移：能按日期或阶段写一篇结构清楚、语言准确的观察日志。 主题与语篇 主题：探索自然、尊重证据、理解生命适应与生态联系。 语篇1 A Journey of Discovery：达尔文在小猎犬号航行中由观察、提问到提出进化观点。 语篇2 The Secret Language of Plants：用举例和类比说明植物通过化学物质、声音和真菌网络交流。 重点识记词汇 seed 种子；distant 遥远的；sample 样本；evolve 进化；suspect 猜想；ancestor 祖先；generate 产生；characteristic 特征；decline 减少；blame 责怪/归咎于；primitive 原始的；detect 发现；root 根；link 联系/连接；centimetre 厘米 阅读认知词汇 disgrace 耻辱；geologist 地质学家；finch 雀科鸣禽；beak 鸟喙；evolution 进化论；tortoise 陆龟；mangrove 红树；iguana 鬣蜥；spine 刺；myth 神话；legend 传说；wasp 黄蜂；pesticide 农药；chilli 辣椒；fungus/fungi 真菌；fungal 真菌的；cybercrime 网络犯罪 词形变化 distant → distance；geologist → geology；evolve → evolution；generate → generation / generator；detect → detection / detective；fungus（复数 fungi）→ fungal 核心词块 answer the call 响应号召；in question 正在讨论的；come to exist 形成；be similar to 与……相似；adapt to 适应；a variety of 多种多样的；be home to 是……的家园；be native to 原产于；tiny amounts of 微量的；drive ... away 赶走；speaking of 说到 重点句型 It was ... who ...（强调句）；It was not ... until ...（直到……才……）；It appears that ...（看来……）；so that ...（以便……）；While A ..., B ...（对比）；the ways in which ...（……的方式） 核心语法 过去完成时：had done；被动式 had been done；表示过去某一时刻或动作之前已经发生或持续的动作。 写作任务 写观察日志：用日期/阶段组织内容，记录条件、变化和结果，并加入简洁感受或推断。 一、核心词汇精讲 1. suspect v. 猜想；怀疑 【用法归纳】suspect that ... 怀疑/猜想……；suspect sb of (doing) sth 怀疑某人做某事。suspect 常表示认为某事很可能属实，doubt 强调不确定或不相信。 【主题例句】Darwin suspected that the finches had evolved from a common ancestor. 【对点训练】Researchers suspected the change ________ being connected with the food available. 【答案】of【解析】suspect sth of doing 为固定搭配。 2. adapt v. 适应；改编 【用法归纳】adapt to sth 适应；adapt oneself to sth 使自己适应；be adapted from ... 改编自……；adaptation n. 适应/改编。 【主题例句】Species survive by adapting to changes in their environment. 【对点训练】The documentary is adapted ________ a book about island wildlife. 【答案】from【解析】表示“改编自”用 be adapted from。 3. generate v. 产生；创造 【用法归纳】generate electricity/heat/ideas 产生电/热/想法；generation n. 产生；一代人；generator n. 发电机。 【主题例句】Careful observation can generate new questions as well as answers. 【对点训练】The discovery has ________ (generate) worldwide interest. 【答案】generated【解析】has 后用过去分词 generated。 4. characteristic n. 特征；adj. 典型的 【用法归纳】a characteristic of ... ……的特征；be characteristic of ... 是……所特有的。作可数名词时常用复数 characteristics。 【主题例句】Different beaks are a characteristic of the finches on different islands. 【对点训练】Patience is characteristic ________ careful field researchers. 【答案】of【解析】be characteristic of 表示“是……所特有的”。 5. decline v./n. 减少；下降；谢绝 【用法归纳】decline by + 幅度；decline to + 数值；decline to do sth 谢绝做某事；a decline in ... ……的下降；in decline 在衰退。 【主题例句】The tortoise population declined after goats were brought to the island. 【对点训练】The number declined ________ 15%, from 2,000 to 1,700. 【答案】by【解析】15% 是下降幅度，用 by。 6. blame v./n. 责怪；归咎于 【用法归纳】blame sb for sth；blame sth on sb；be to blame for ... 应对……负责（主动形式表示被动意义）；take the blame for ... 承担责任。 【主题例句】Human activity is often blamed for the loss of island species. 【对点训练】No single person is ________ (blame) for the failed experiment. 【答案】to blame【解析】be to blame 是固定结构，不用 to be blamed。 7. detect v. 发现；察觉 【用法归纳】detect a change/signal 发现变化/信号；detection n. 发现；detective n. 侦探。detect 强调发现不易察觉的事物。 【主题例句】Sensitive equipment can detect tiny sounds made by plant roots. 【对点训练】Early ________ (detect) of the disease can protect the whole forest. 【答案】detection【解析】形容词 early 后接名词 detection。 8. link v./n. 联系；连接 【用法归纳】link A to/with B；be linked to/with ...；a link between A and B。注意 between 后搭配 and。 【主题例句】In a forest, plants may be linked underground by a fungal network. 【对点训练】Scientists found a close link ________ rainfall and seed production. 【答案】between【解析】a link between A and B 为固定结构。 二、核心语法精讲：过去完成时 基本形式 肯定：had done；否定：had not done；疑问：Had + 主语 + done?；被动：had been done。 核心意义 以过去某个时间或动作为参照，表示在此之前已经完成或已经持续的动作，即“过去的过去”。 常见标志 by/before + 过去时间；by the time + 一般过去时；when/before/after 引导的过去时间从句；already、just。 固定结构 Hardly/Scarcely had sb done when ...；No sooner had sb done than ...；It was the first/second time that sb had done。 易错提醒 若 before/after 已清楚表明先后，较早动作有时可用一般过去时代替过去完成时；只有存在明确的过去参照点时才使用过去完成时。 1. By the end of the voyage, Darwin ________ (collect) many samples. 【答案】had collected【解析】by the end of + 过去时间提示过去完成时。 2. When the researchers arrived, the birds ________ (leave) the island. 【答案】had left【解析】鸟离开发生在研究者到达之前。 3. The rare plant ________ already ________ (detect) before the report was published. 【答案】had; been detected【解析】植物是被发现，用过去完成时的被动式。 4. Hardly ________ the rain stopped when insects began to appear. 【答案】had【解析】Hardly 位于句首，主句部分倒装。 5. It was the first time that the students ________ (record) the complete growth cycle. 【答案】had recorded【解析】It was the first time that ... 后用过去完成时。 三、单元写作清单：观察日志 1. 话题分析 观察日志以真实观察为基础，重点写清时间、条件、显著变化和结果。可以按日期分条，也可以按生长阶段分段；语言应客观、准确，末尾可加入简短感受或推断。 2. 写作框架 开头：交代观察对象、起始时间和初始条件。 主体：按时间顺序记录可见变化，并用数据、颜色、形状或行为支持描述。 结尾：总结结果，写出感受、问题或下一步观察计划。 3. 写作素材 顺序：at first, a few days later, gradually, over the following week, by the end of ...； 变化：sprout, soften, take root, grow upwards, reach ... cm, develop leaves, produce a bud, bloom； 表达：It took ... days for ... to ...；With time going by, ...；By ..., ... had ...；What surprised me most was ... 4. 范文示例 15 March I placed four soaked mung bean seeds on damp cotton in a clear cup and left it beside the window. The seeds were pale green and their coats were still hard. 18 March Three seeds had split open. A short white root had pushed downwards from each seed, while a tiny green shoot was beginning to point upwards. I added only a few drops of water. 25 March The shoots had reached about eight centimetres. Two fresh leaves had unfolded on each plant, and the roots formed a fine network against the cup. The plant nearest the light was the tallest. 5 April All three plants had grown stronger, but one leaned towards the window. The change showed me how closely growth is linked to light and water. I will turn the cup regularly in the next stage. 易错点01 一般过去时与过去完成时 【错因辨析】先找过去参照点，再判断哪个动作更早。不能因为句子谈过去就机械使用 had done。 【对点训练】When the scientist opened the box, the insect ________ (escape). 【答案】had escaped【解析】昆虫逃走发生在 opened 之前。 易错点02 be to blame 的形式 【错因辨析】be to blame 表示“应负责任”，主动形式含被动意义；不能写成 be to be blamed。 【对点训练】Human carelessness was ________ (blame) for the fire. 【答案】to blame【解析】固定结构 be to blame for。 易错点03 decline 的搭配 【错因辨析】decline by 后接幅度，decline to 后接最终数值；表示“谢绝做某事”用 decline to do。 【对点训练】The population declined ________ 900 ________ 650 in two years. 【答案】from; to【解析】from ... to ... 表示从一个数值下降到另一个数值。 易错点04 adapt 与介词 【错因辨析】adapt to 表示适应；be adapted from 表示改编自；be adapted for 表示为某用途改编/改造。 【对点训练】Animals must adapt ________ seasonal changes to survive. 【答案】to【解析】adapt to 为固定搭配。 建议用时：30分钟　满分：45分 一、默写重点单词（每题1分，共8分） 1. __________ n. 样本 2. __________ v. 进化 3. __________ v. 猜想；怀疑；觉得 4. __________ n. 祖先；原种 5. __________ v. 产生；创造 6. __________ n. 特征；特性 7. __________ v. 发现；察觉 8. __________ v. 把……联系起来；连接 【答案】1. sample 2. evolve 3. suspect 4. ancestor 5. generate 6. characteristic 7. detect 8. link 二、词汇与短语运用（每题1分，共6分） 9. The researchers collected several rock ________ (sample) during the journey. 10. A species may disappear if it cannot adapt ________ rapid environmental change. 11. Her careful notes helped ________ (generate) a new question about seed growth. 12. The number of wild goats declined ________ 1,200 to 800 in five years. 13. No single factor is ________ (blame) for the sudden change. 14. New evidence links the decline ________ the loss of wetland plants. 【答案】9. samples 10. to 11. generate 12. from 13. to blame 14. to/with 三、重点句型与语法（每题1分，共6分） 15. By the time the ship returned, Darwin ________ (collect) a large number of samples. 16. When Darwin reached the islands, he found that the finches ________ (develop) different beaks. 17. It was not until 1859 ________ Darwin's book was published. 18. Hardly ________ the rain ________ (stop) when the frogs began to call. 19. No sooner ________ the students set up the camera than a fox appeared. 20. The team completed the fieldwork. Then they compared the samples.（用过去完成时合并） 【答案】15. had collected 16. had developed 17. that 18. had; stopped 19. had 20. After the team had completed the fieldwork, they compared the samples. 四、写作微任务（共5分） 21. 根据以下观察记录写一段约80词的向日葵观察日志：Day 1，播下5粒种子；Day 4，3粒发芽；Day 10，茎约8厘米并长出两片叶；Day 24，出现第一个花蕾。要求时间顺序清楚，至少使用1处过去完成时。 【评分建议】内容完整2分；顺序与衔接1分；过去完成时使用准确1分；语言与书写1分。 【答案】Day 1: I planted five sunflower seeds in moist soil and put the pot near a sunny window. Day 4: Three seeds had sprouted, each with a tiny pale-green shoot. Day 10: The stems had reached about eight centimetres and two fresh leaves had unfolded. I turned the pot so that the plants could receive light evenly. Day 24: The first flower bud had appeared at the top of the strongest stem. Watching these small changes made me realise how patiently nature works. 五、阅读理解（每题4分，共20分） Each spring, rain fills shallow hollows in a woodland near Hangzhou, creating temporary pools that vanish by midsummer. For years, hikers treated them as muddy puddles. In 2024, students from a nearby school noticed strings of frog eggs in one pool and asked why frogs chose water that would soon disappear. Under the guidance of a biologist, the group mapped twelve pools, recorded water temperature and depth each week, and installed small cameras. They did not handle the animals. Instead, they photographed the same one-metre areas and used one counting method on every visit. At first, they assumed the deepest pools would support the most young frogs. Early data seemed to agree: those pools held water longer and contained more tadpoles. Then the camera recordings changed the story. Fish had entered two of the deepest pools after a stream overflowed. Wherever fish appeared, tadpole numbers dropped sharply. The finding revealed a trade-off. Temporary pools do not offer permanent security; their value lies in a brief window. If the water disappears too early, tadpoles cannot complete their change into frogs. If it lasts too long and connects with a stream, predators may arrive. The most successful pools were not the deepest but those that held water long enough while remaining separate. This did not mean the shallowest pools were always best: three dried during an unusually hot week and lost nearly all their tadpoles. The students repeated the observations the following spring before drawing a conclusion, and the pattern returned. Instead of 'fixing' the pools by digging them deeper, the school worked with park managers to protect a variety of depths and the natural routes followed by rainwater. Fallen leaves were left at the edges because they shaded the water and supported tiny organisms that tadpoles ate. New signs now ask visitors to avoid trampling the pools during the breeding season. The project changed how the students saw ordinary places: a short-lived puddle was not an unfinished pond but a habitat shaped by timing. Nature's clues had been present all along; careful measurement revealed what a quick look had missed. 22. What first led the students to investigate the temporary pools? A. Fish were seen leaving a stream. B. Frog eggs were found in a pool that would soon vanish. C. Park managers planned to deepen the pools. D. Hikers reported that the woodland was flooding. 【答案】B【解析】第一段说明学生看到蛙卵后产生了研究问题。 23. Which evidence made the students revise their first assumption? A. Deep pools changed temperature more slowly. B. Fish entered deep pools and tadpole numbers there fell. C. Shallow pools received less rain than expected. D. Cameras showed hikers walking near the pools. 【答案】B【解析】鱼进入深水池后，蝌蚪数量显著下降，推翻了“越深越好”的初步假设。 24. What does the phrase 'a brief window' in Paragraph 3 refer to? A. A place where students could watch the animals. B. A season when every pool stayed completely safe. C. A limited period when water lasted long enough but predators stayed away. D. A short break between two weekly research visits. 【答案】C【解析】下文从过早干涸与持续过久两方面解释了适宜时间窗口。 25. Why did the students repeat the observations the following spring? A. To check whether the pattern was reliable beyond one season. B. To find a safer way to handle the tadpoles. C. To compare their results with hikers' photographs. D. To prove that the deepest pool was the most useful. 【答案】A【解析】跨季节重复观察可降低偶然天气造成的误判。 26. Which title best expresses the main idea of the passage? A. How to Build a Permanent Woodland Pond B. Why Fish Are Disappearing from City Streams C. A School Camera Project That Failed D. When a Temporary Puddle Becomes a Nursery 【答案】D【解析】文章核心是短暂水池在恰当时间条件下成为蛙类繁殖地。 六、检测答案速查 Ⅰ 1 sample；2 evolve；3 suspect；4 ancestor；5 generate；6 characteristic；7 detect；8 link Ⅱ 9 samples；10 to；11 generate；12 from；13 to blame；14 to/with Ⅲ 15 had collected；16 had developed；17 that；18 had, stopped；19 had；20 见题后示例 Ⅳ 21 按评分标准给分 Ⅴ 22 B；23 B；24 C；25 A；26 D 学科网（北京）股份有限公司1 / 10 学科网（北京）股份有限公司 $