新概念英语第三册 Lesson 1 A Puma at Large 学习要点解析 讲义

新概念英语第三册 Lesson 1 学习要点全解析 一、词汇用法 puma 【释义】可数名词，指 “美洲狮”，是一种大型猫科动物。 【例句】A puma is a powerful predator.（美洲狮是强大的掠食者。） 【搭配】spot a puma（发现美洲狮）；hunt a puma（猎捕美洲狮） at large 【释义】短语副词，意为 “逍遥法外；未被捕获；一般地；普遍地；自由地”。 【例句】The criminal is still at large.（罪犯仍逍遥法外。） / The news spread at large.（这个消息广泛传播。） spot 【释义】 动词：“发现；认出；看见；弄脏；使有斑点”。 名词：“地点；斑点；污渍；少量”。 【例句】 动词：I spotted a mistake in your report.（我在你的报告中发现了一个错误。） 名词：This is the very spot where the accident happened.（这就是事故发生的地点。） 【搭配】on the spot（当场；在现场）；a beauty spot（美人痣；风景区） evidence 【释义】不可数名词，“证据；根据；迹象”。 【例句】There is not enough evidence to convict him.（没有足够的证据定他的罪。） 【搭配】gather evidence（收集证据）；present evidence（出示证据） accumulate 【释义】动词，“积累；积聚；堆积”。 【例句】Over the years, he has accumulated a great fortune.（多年来，他积累了一大笔财富。） 【搭配】accumulate wealth（积累财富）；accumulate experience（积累经验） oblige 【释义】动词，“迫使；使感激；施惠于；帮忙”，常用 “feel obliged to do sth.” 结构，表示 “觉得有义务做某事；不得不做某事”。 【例句】I feel obliged to help you.（我觉得有义务帮助你。） 【搭配】be obliged to sb. for sth.（因某事感激某人） hunt 【释义】 名词：“狩猎；搜寻；追捕”。 动词：“打猎；搜寻；追捕；追逐”。 【例句】 名词：The hunt for the lost treasure has lasted for centuries.（寻找丢失宝藏的行动已经持续了几个世纪。） 动词：We are hunting for a new house.（我们正在寻找一所新房子。） 【搭配】go on a hunt（去打猎；去搜寻）；hunt down（追捕到；搜寻到） corner 【释义】 名词：“角落；拐角；困境；偏僻处”。 动词：“使陷入绝境；把… 难住；转弯；囤积”。 【例句】 名词：There is a bookshelf in the corner of the room.（房间的角落里有一个书架。） 动词：The police cornered the thief in an alley.（警察把小偷逼在一条小巷里。） 【搭配】around the corner（在拐角处；即将来临）；cut corners（抄近路；节省开支） trail 【释义】 名词：“踪迹；痕迹；小路；一连串；一缕”。 动词：“跟踪；追踪；拖；拉；蔓延”。 【例句】 名词：The hikers followed the mountain trail.（徒步旅行者沿着山间小路前行。） 动词：The dog trailed its leash behind it.（狗拖着它的皮带。） 【搭配】leave a trail（留下踪迹）；trail off（逐渐减弱；缩小） 二、课文精讲 课文开篇引入美洲狮这一主题，介绍其特征及分布，随后提及伦敦动物园收到在伦敦南部发现野生美洲狮的报告，起初未受重视。 【原文】“Pumas are large, cat-like animals which are found in America. When reports came into London Zoo that a wild puma had been spotted forty-five miles south of London, they were not taken seriously.” 【解析】此句中 “which are found in America” 是定语从句，修饰 “animals”，描述美洲狮的生存地域；“that a wild puma had been spotted...” 是同位语从句，对 “reports” 的内容进行解释说明。 随着相关证据不断增多，动物园专家们意识到需要展开调查，因为目击者对美洲狮的描述极为相似。 【原文】“However, as the evidence began to accumulate, experts from the Zoo felt obliged to investigate, for the descriptions given by people who claimed to have seen the puma were extraordinarily similar.” 【解析】“as” 引导时间状语从句，表示 “随着”；“feel obliged to do sth.” 表达 “感到有责任做某事”；“given by people who claimed to have seen the puma” 是过去分词短语作定语，修饰 “descriptions”，其中 “who claimed to have seen the puma” 为定语从句，修饰 “people”。 搜寻行动于一个小村庄启动，一位妇女曾在此处近距离目睹 “大猫”，其受惊逃窜。专家同时指出，美洲狮除非走投无路，一般不会主动攻击人类。 【原文】“The hunt for the puma began in a small village where a woman picking blackberries saw 'a large cat' only five yards away from her. It immediately ran away when she saw it, and experts confirmed that a puma will not attack a human being unless it is cornered.” 【解析】“where a woman picking blackberries...” 是定语从句，修饰 “village”，“picking blackberries” 是现在分词短语作后置定语，修饰 “woman”；“unless” 引导条件状语从句，意为 “除非”。 整个搜寻过程困难重重，美洲狮行动诡秘，常于早晚出没于不同地点，所经之处留下诸多踪迹，包括死鹿、小动物尸体、爪印、皮毛等，还有人声称听到猫叫，一位商人也曾见其在树上。 【原文】“The search proved difficult, for the puma was often observed at one place in the morning and at another place twenty miles away in the evening. Wherever it went, it left behind it a trail of dead deer and small animals like rabbits. Paw prints were seen in a number of places and puma fur was found clinging to bushes. Several people complained of 'cat-like noises' at night and a businessman on a fishing trip saw the puma up a tree.” 【解析】“for” 引导原因状语从句；“Wherever it went” 为让步状语从句；“clinging to bushes” 是现在分词短语作宾语补足语。 最终专家确定此动物为美洲狮，但其来源成谜。鉴于国内无动物园报告美洲狮失踪，推测其可能为私人收藏家所有并逃脱。尽管搜寻持续数周，美洲狮仍下落不明，这一情况令人忧心乡村仍有危险野生动物游荡。 【原文】“The experts were now fully convinced that the animal was a puma, but where had it come from? As no pumas had been reported missing from any zoo in the country, this one must have been in the possession of a private collector and somehow managed to escape. The hunt went on for several weeks, but the puma was not caught. It is disturbing to think that a dangerous wild animal is still at large in the quiet countryside.” 【解析】“be convinced that...” 表示 “确信…”；“must have been” 表示对过去情况的肯定推测；“It is disturbing to think that...” 中 “it” 作形式主语，真正主语是 “to think that...”。 三、语法点：现在完成进行时 【构成】“have/has been + 动词的现在分词”。例如：He has been working on this project for months.（他已经为这个项目工作了好几个月。） 【用法】 表示从过去某一时间开始一直持续到现在的动作或状态，并且可能还会继续下去。如：I have been learning English since I was a child.（我从小就一直在学习英语。）强调学习英语这个动作从过去开始，持续到现在，未来可能还会继续。 强调动作的持续性和不间断性。与现在完成时相比，更侧重动作过程。例如：“I have written a letter.”（我写了一封信，动作已完成）“I have been writing a letter.”（我一直在写信，强调写信过程一直在进行，可能未完成）。 常与 “since + 时间点”“for + 时间段” 等时间状语连用。例如：She has been living in this city for ten years.（她在这个城市已经住了十年了。） 四、习题 用所给单词的适当形式填空 The police have been ______ (hunt) for the escaped criminal for weeks. Evidence has been ______ (accumulate) against the suspect. She felt ______ (oblige) to tell the truth. The ______ (spot) where the accident happened was marked with a sign. The dog has left a ______ (trail) of footprints in the snow. 单项选择 The puma is an animal ______ is native to America. A. which B. who C. whom D. where Experts felt obliged to investigate because the descriptions were ______. A. ordinary B. similar C. different D. strange A puma will not attack a human being ______ it is cornered. A. if B. unless C. because D. although The hunt for the puma proved difficult ______ its elusiveness. A. because of B. because C. since D. as It is disturbing to think that the dangerous animal is still ______. A. caught B. in prison C. at large D. hunted 翻译句子 随着时间的推移，他积累了丰富的知识。（accumulate） 警察把小偷逼到了一个角落里。（corner） 我觉得有义务帮助那些有困难的人。（feel obliged to） 至今还没有发现那只美洲狮的踪迹。（trail） 除非被邀请，否则我不会去参加聚会。（unless） 五、习题答案 用所给单词的适当形式填空 hunting（have been doing 现在完成进行时） accumulating（现在完成进行时的被动语态） obliged（feel obliged to do sth.） spot（名词，地点） trail（名词，踪迹） 单项选择 A（定语从句，先行词是 animal，关系代词用 which） B（根据课文内容，描述相似所以专家才调查） B（unless 除非，符合课文中美洲狮习性描述） A（because of 后接名词短语，because 后接句子，这里 its elusiveness 是名词短语） C（at large 逍遥法外，符合文意） 翻译句子 As time passes by, he has accumulated a wealth of knowledge. The police cornered the thief in a corner. I feel obliged to help those who are in trouble. No trail of the puma has been found so far. I won't go to the party unless I am invited. 学科网（北京）股份有限公司 $$