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A卷Ⅰ单项填空1．One important aim of our school is to prepare us for the future ________ we can face all the challenges with confidence.A．in that B．even ifC．so that D．as ifC解析：考查状语从句. 句意：我们学校的一个重要目的就是让我们为未来做好准备，以便我们能够满怀信心地面对所有挑战. 根据句意可知，这里用so that 引导目的状语从句，表示“以便”.2．A baby born with the virus that causes AIDS appears ________，scientists announced on Sunday, describing it is only the world’s second reported cure.A．cured B．being curedC．to be cured D．to have been curedD解析：考查非谓语动词. 句意：科学家们星期天宣布：一个生来就携带艾滋病病毒的婴儿似乎被治愈了，这是世界上已报道的第二例. appear to do sth.是固定句式，根据句意可知，这个孩子似乎“已经被治愈了”，A baby与cure之间是动宾关系并且动作已经完成，所以选D项.3．Those workers told the reporters that though they were doing dirty and tiring work, they still wanted to work with ________．A．privilege B．benefitC．dignity D．evidenceC解析：考查名词辨析. 句意：那些工人们告诉记者虽然他们干的是脏活累活，但他们仍然希望能有尊严地工作. 选择dignity “尊严”符合句意. privilege “特权”；benefit “利益，好处”；evidence “证据”.4．They have decided to show the children around the small town because the brightly colored houses there ________children.A．appeal to B．appeal forC．cater to D．cater forA解析：appeal to (sb.) “吸引某人”；appeal for “呼吁”；cater to “迎合；投合(口味、爱好……)”；cater for “满足……的要求”. 根据句意以及空格后的children可判断答案应为A项.5．The most important thing to do when ________an emergency is ________calm.A．dealing with; stay B．dealt with; to stayC．deal with; to stay D．dealt with; stayA解析：根据后面的an emergency可判断第一空应用dealing with表主动；当主语部分含有实意动词do, 后面的不定式作表语时可以省略to.6．Due to cultural differences, most artists find it hard to________Chinese cross-talk to westerners.A．get across B．take overC．come across D．come overA解析：句意：由于文化差异，大部分艺术家发现很难把中国的相声传达给西方人. get across “将……传达给某人；讲清楚”；take over “接管”；come across “偶然发现”；come over “拜访；突然感到”. 根据句意可知答案为A项.7．(2018·盐城中学高三综合测试)Diplomatic communication is ongoing between Beijing and Tokyo________at avoiding a major conflict________the islands, said Shen Shishun, an expert on AsiaPacific studies at Haikou College of Economics.A．aimed; regarding B．aiming; consideringC．meant; concerning D．aiming; givenA解析：第一空aimed at... “旨在……”作状语；第二空regarding＝concerning介词“关于”，作定语修饰conflict.8．More and more students are________reading in our school.A．benefiting from B．comparing toC．giving off D．setting outA解析：句意：在我校，越来越多的学生正从阅读中受益. benefit from “从……中受益”.9．Smith was overweight, so the doctor urged that not only________have less fat and meat, but also he________．A．should he; take exerciseB．ought he; take exerciseC．he should; takes exerciseD．he ought; takes exerciseA解析：urge后跟宾语从句时，从句的谓语动词用(should) do. 句意：史密斯太胖，因此医生敦促他不仅要少食脂肪和肉，而且要进行锻炼.10．I recommend that the planning________until all the materials have been supplied.A．is not started B．will not be startedC．not be started D．is not to be startedC解析：句意：我建议当所有的材料都准备好以后再开始实施那个计划. recommend后面的从句谓语动词要用“should＋动词原形”，should可以省略，故选C.11．—What about the person?—Seldom in all my life________such a________ person.A．I met; determiningB．I have met; determiningC．did I meet; determinedD．have I met; determinedD解析：seldom是否定副词，位于句首时句子用部分倒装，因此排除A、B两项；根据句意可知第一个空表示到现在为止的动作，因此用现在完成时；determined是形容词，意为“意志坚定的”.12．Nine in ten parents said there were significant differences in their approach to educating their children compared with ________ of their parents.A．those B．oneC．both D．thatD解析：考查代词的用法. 句意：十分之九的父母说，他们教育孩子的方法与自己父母的方法大不相同. approach此处是特指，为单数，故为that代替. one为同类泛指.13．(2018·江苏四市调研)Look, ________beautiful flowers________the girl carrying that she becomes the focus in the room.A．such; is B．so; areC．how; is D．what; areA解析：句意：看，那个女孩正拿着如此漂亮的花以至于她变成了房间里的焦点. 根据句型such＋形容词＋名词复数/不可数名词＋助动词＋主语＋that...，可知选A.14．(2018·淮安中学期中)If you go to the souvenir shops in places of interest, sometimes you can’t help_________________into buying something fake.A．to persuade B．persuadingC．be persuaded D．being persuadedD解析：考查固定结构. can’t help doing sth. “忍不住做某事”，且you和persuade 是动宾关系，所以选D. 句意：如果你去风景区的纪念品商店，有时你忍不住被说服买一些假货.15．________ by the advances in technology, many farmers have set up wind farms on their land.A．Being encouragedB．EncouragingC．EncouragedD．Having encouragedC解析：考查非谓语动词. 句意：受科技进步的激励，很多农民在他们的土地上建了风力发电场. C项是过去分词表被动、完成，作原因状语，符合题意；A项是现在分词的被动式，表示被动和正在进行；B项是现在分词，表主动和正在进行；D项是现在分词的完成时，表主动且发生在谓语动词的动作之前.Ⅱ阅读理解Joseph Goldberger was a doctor for the United States Public Health Service and he was an advocate for scientific and social recognition of the links between poverty and disease. In 1914, Goldberger was asked by U．S. Surgeon General Rupert Blue to study a skin disease that was killing thousands of people in the South. The disease was pellagra(糙皮病)．Goldberger traveled to the state of Mississippi where many people suffered from pellagra. He studied the victims and their families. Most of the people lived a hard life. The doctor came to believe that the disease didn’t pass on from one to another, but was instead related to food. He received permission from the state governor to test this idea at a prison. Prisoners were offered pardons if they took part. One group of prisoners received their usual foods, mostly corn products.A second group ate meat, fresh vegetables and drank milk. Members of the first group developed pellagra. The second group did not.But some medical researchers refused to accept Goldberger’s idea. For the South, pellagra was more than simply a medical problem. There were other things, including Southern pride.So Goldberger had himself injected(注射) with blood from a person with pellagra. He also took liquid from the nose and throat of a pellagra patient and put them into his own nose and throat. He even swallowed pills that contained skin from pellagra patients. An assistant also took part in the experiments. So did Goldberger’s wife. None of them got sick.Joseph Goldberger died of cancer in 1929. He was fiftyfive years old. Several years later, researchers discovered the exact cause of pellagra：a lack of vitamin B3 known as niacin.【解题导语】本文是一篇记叙文.文章介绍了美国医生Joseph Goldberger研究糙皮病的患病原因的过程.Joseph Goldberger医生的认真、牺牲精神令人感动.1．Who were easy targets of pellagra according to Goldberger?A．People in America.B．People put into prison.C．People having a poor diet.D．People touching pellagra patients.C解析：细节理解题.根据第二段中的“Most of the people lived a hard life...the disease didn’t pass on from one to another, but was instead related to food.”，再结合Goldberger在监狱进行的实验的内容可知，在Joseph Goldberger看来，糙皮病和食物有关，而且患者大多生活条件差；再结合实验中提到的主要吃玉米制品的犯人最后患上了该病可知，不良的饮食容易导致人们患糙皮病.2．What did Goldberger want to prove by the experiments mentioned in Paragraph 4?A．Pellagra wasn’t so terrible.B．Pellagra didn’t spread.C．Pellagra could be cured.D．Pellagra wasn’t a medical problem.B解析：推理判断题.根据第二段中提到的Goldberger认为糙皮病不是传染病以及第四段中提到的他为了证明自己的观点而进行的实验的内容(将患糙皮病的人的血液注射到自己的体内、将糙皮病病人的鼻腔和口腔中的液体放入自己的鼻腔和口腔以及吞咽含有糙皮病病人的皮肤组织的药丸)和结果(他没患病)可推知，Goldberger进行实验是为了证明糙皮病不传染.3．Which words can be used to describe Goldberger?A．Devoted and determined.B．Selfless and friendly.C．Patient and expert.D．Stubborn and enthusiastic.A解析：推理判断题.文中提到的Goldberger在监狱及在他自己身上做实验的内容表明他全心全意地投入到对糙皮病的研究中，有奉献精神；尽管一些人不认可Goldberger的观点，但他仍坚持自己的看法并坚决地去证明自己的观点是正确的，这体现出他意志坚定.故选A.Ⅲ任务型阅读(2018·江苏时堰中学第一次测试)When you feel disappointed, you should know it is natural and normal, and everyone will experience it to some extent in their life.Sometimes life deals us a difficult hand, and events and trials arise that we have no control over.Other times it is our own actions themselves that cause our trials.Regardless of the nature of our trials, disappointment is part of life’s journey and how we deal with it will largely determine the quality of our life.Here are some steps to help us to make our journey more enjoyable.Firstly, redefine our rules.It is assumed that everyone has an internal “rule”in their mind.If our internal rules are too perfect, then they will discourage us greatly.For example, if we have a rule that says we need to be perfect, it is likely that we will spend a large amount of time feeling sad and disappointed.So when we feel disappointed, it is wise to review and redefine our rules.Want an example of an encouraging rule? Try this one: I am happy and I am successful since I have made my greatest efforts.Secondly, remind ourselves now and then of the reasons why we are seeking the very goal.As a matter of fact, there are many cases where we have forgotten our original purposesalong the way.So it is of great help to remember the reasons why we are committed to a path in the first place when we feel down.By revisiting those reasons, we will likely renew our commitment and not get hung up on the disappointment of the moment.Thirdly, think about our larger vision and recommit to it.Disappointment is merely a setback on what will eventually be a great and inspiring journey.So when we have those momentary setbacks, it is helpful to think about our larger vision and recommit to it.In our larger vision, therefore, a disappointment is a very valuable experience, which serves as a good educator and makes us more able to meet the challenges of the future.Finally, reset and have a new start.Resetting and starting anew prevents us from abandoning ourselves to self-pity and forces us to get up and move forward.Don’t live in the past.Take what the past has taught us and keep moving.Wake up the very next day as if our whole life is ahead of us and we have the chance to start fresh.Nothing that happened in the past can stop us from creating the life that we have always desired or from accomplishing the goals that we are seeking.6.Remember/Revisit/Recall7．reminded8.capable9.learned/learnt10.qualityB卷Ⅰ完形填空Honesty is always the best policy，especially when it comes to mental health problems. In aTV __1__，one girl gets very real about dealing with anxiety and panic.“I was the best student in my high school. I put so much __2__ on myself，”she said. “I never __3__a class. But I got sick during 10th grade and I started to __4__. That was when the panic attacks began.”She goes on to describe what a panic attack __5__ like，“One day the teacher handed me my grade __6__，and I couldn’t breathe. My heart was beating very __7__. I felt disconnected. I saw people trying to talk to me but I couldn’t hear them. Afterwards，I was sent to __8__，”she shared.It was then __9__ the attacks started happening __10__ daily，and they haven’t stopped. “Last year I started college. And I can’t be the best student here no matter how hard I try，”she said. “Everyone is so __11__. My panic attacks got so bad that I had to __12__ my first semester.”However，now she is facing her anxiety，and things are getting better. “I used to try to hide __13__. I thought that __14__ nobody knew，it would not exist，”she said. “But the more I talk about my __15__，the more I realize that other people experience __16__ things. So I’m trying to express it more. I had a great teacher __17__ told me，‘Instead of letting anxiety keep you from doing your art，let it be the thing that __18__your art.’”Recently，women all over the world took to Twitter to __19__ what anxiety is like. We are __20__ alone.【解题导语】本文是一篇夹叙夹议文.一个女孩分享了她曾经的焦虑经历，后来，她勇敢面对焦虑，情况得以好转.作者借这个事例说明直面困难、坦陈问题往往是解决心理健康问题的良策.1．A.project B．programC．platform D．stationB解析：根据“In a TV ______，one girl gets very real about dealing with anxiety and panic.”可知，在一个电视节目(program)中，一个女孩坦诚地分享了她克服焦虑和惊恐的经历，故B项正确.A项意为“项目”，C项意为“平台”，D项意为“站”，都与语境不符.2．A.weight B．heightC．pressure D．measureC解析：根据前一句“I was the best student in my high school.”再结合该句“I put so much ______ on myself”可知，该句是说，在学校里这个女孩是一位优等生，她自己给自己施加了很多压力.C项意为“压力”，符合语境，故C项正确.A项意为“体重”，B项意为“身高”，D项意为“度量单位”，都与语境不符.3．A.joined B．succeededC．failed D．attendedC解析：根据上文，再结合该句“I never ______a class.”可知，这个女孩从没有考试不及格过；C项意为“不及格”，符合语境，故C项正确.A项意为“加入”；B项意为“成功”；D项意为“参加”.4．A.fall behind B．fall downC．leave behind D．leave aloneA解析：根据上下文可知，在十年级时这个女孩生病了，成绩开始落后；A项意为“落后”，符合语境，故A项正确.B项意为“跌倒；失败”；C项意为“留下，遗留”；D项意为“不打扰”.5．A.looks B．soundsC．tastes D．feelsD解析：根据空处前后句可知，这个女孩是在描述焦虑症发作时的感觉.feel like为固定搭配，意为“感觉像是……”，符合语境，故D项正确.6．A.report B．surveyC．research D．noticeA解析：根据该句中“One day the teacher handed me my grade ______，and I couldn’t breathe.”可知，老师将成绩单交给了这个女孩；表示“成绩单”用“grade report”，故A项正确.7．dly B．wildlyC．slowly D．severelyB解析：根据后一句“I felt disconnected.”可以判断，这个女孩看到了她的成绩单后感觉无法呼吸，心脏疯狂地(wildly)跳动，故B项正确.A项意为“温和地”；C项意为“缓慢地”；D项意为“严格地”.8．A.school B．workC．hospital D．homeC解析：参见上题解析并结合该句“Afterwards，I was sent to ______”可以判断，最后，这个女孩被送往医院.故C项正确.9．A.when B．sinceC．before D．thatD解析：根据该句“It was then ______ the attacks started happening ______ daily，and they haven’t stopped.”可知，该句使用了强调句型，被强调的部分是then，故用that引导句中的其他部分，故D项正确.10．A.still B．alwaysC．merely D．almostD解析：根据空处所在句可知，从那时起焦虑几乎每天发生，没有停止过.D项意为“几乎”，符合语境，故D项正确.11．A.ambitious B．anxiousC．talented D．experiencedC解析：根据空处前一句可知，在大学里，无论这个女孩怎么努力都无法成为最好的学生；结合该句“Everyone is so ______．”可知，每个人都有天赋；C项意为“有天赋的”，符合语境，故C项正确.12．A.arrange B．performC．operate D．cancelD解析：根据该句“My panic attacks got so bad that I had to ______ my first semester.”可知，这个女孩的焦虑症变得如此严重，她不得不休学.D项意为“取消”，符合语境，故D 项正确.13．A.it B．themC．me D．usA解析：根据空处前后句可知，空处指代前一句的“anxiety”，后一句中的“it would not exist”也是提示.故此处用it.14．A.unless B．ifC．while D．asB解析：根据语境可知，空处引导条件状语从句，故此处用if.15．A.confidence B．dreamC．issue D．desireC解析：根据上下文可知，空处是指这个女孩的焦虑问题.C项意为“问题”，符合语境，故C项正确.A项意为“信心”；B项意为“梦想”；D项意为“渴望”.16．A.similar B．familiarC．various D．seriousA解析：根据上下文可知，此处是指这个女孩对她的问题谈得越多，她就越意识到其他人也经历过相似的事情.文章的最后一段也是提示.故A项正确.17．A.who B．whomC．whose D．whichA解析：分析该句结构可知，该句为定语从句，先行词为“a great teacher”，在从句中作主语，故用who引导该定语从句.18．A.abandons B．quitsC．motivates D．protestsC解析：根据语境可知，空处应用与“keep you from doing your art”意义相反的一个动词.C项意为“激励”，符合语境，故C项正确.A项意为“放弃”；B项意为“停止”；D 项意为“反对”.19．A.advertise B．adviseC．share D．compareC解析：根据该句“Recently，women all over the world took to Twitter to ______ what anxiety is like.”可知，最近，世界各地的女性都在推特上分享了焦虑的经历.C项意为“分享”，符合语境，故C项正确.20．A.always B．sometimesC．seldom D．neverD解析：参见上题解析，再结合该句“We are ______ alone.”可知，焦虑者不是孤独的，故用否定词never.Ⅱ阅读理解AElon Musk was born in South Africa, in 1971. A crazy fan ofcomputers, by the age of twelve, Musk had written the code(代码) forhis own video game, which he sold for a profit.He attended Queen’s University in Canada, and transferred(转到)to the University of Pennsylvania, where he earned two bachelor’s degrees, economics and physics. He was admitted to Stanford University in California, intending to earn a PhD in energy physics.First Company—Zip2 CorporationIn 1995, at the age of 24, Musk dropped out of Stanford University after just two days of classes to start his first company Zip2 Corporation. It was an online city guide that provided content for the new online versions of The Ne w York Times and the Chicago Tribune newspapers. In 1999, Musk got $ 22 million from the sale of Zip2.Online BankingIn 1999, Elon Musk started X．com with $ 10 million dollars from the sale of Zip2. X. com was an online bank, and he was credited with inventing a method of securely transferring money using a receiver’s e-mail address.PayPalIn 2000, X. com bought a company called Confinity, which had started an Internet moneytransfer process called PayPal. Elon Musk dropped the online banking focus to concentrate on becoming a global payment transfer provider. In 2002, eBay bought PayPal for $ 1.5 billion. Space Exploration TechnologiesIn 2002, Elon Musk started SpaceX. He is a longstanding member of the Mars Society, a nonprofit organization that supports the exploration of Mars, and Musk is interested in building agreenhouse on Mars. SpaceX has been developing rocket technologies to enable Musk’s project. Tesla MotorsIn 2004, Elon Musk cofounded Tesla Motors, of which he is the only product architect. Tesla Motors builds electric vehicles. The company has built an electric sports car, the Tesla Roadster. SolarCityIn 2006, Elon Musk cofounded SolarCity, a photovoltaic(光电的) products and services company with his cousin Lyndon Rive.【解题导语】本文是一篇记叙文，主要介绍了埃隆·马斯克的人生经历和伟大成就.1．What was Elon Musk gifted in when he was young?A．Economics.B．Physics.C．Energy. D．Coding.D解析：细节理解题.根据第一段的第二句可知，Musk是一位疯狂的电脑迷，十二岁时他就为自己的视频游戏写代码并获利了；据此可知，他小时候就有写代码的天赋，故D 项正确.2．Which of the following provides international payment transfer service?A．. B．Confinity.C．PayPal. D．eBay.C解析：细节理解题.根据PayPal部分，尤其是该部分的第二句可知，PayPal提供国际转账支付服务，故C项正确.3．What has SpaceX been doing to help achieve Musk’s project?A．Sponsoring the Mars Society.B．Developing rocket technologies.C．Building a greenhouse on Mars.D．Supporting the exploration of Mars.B解析：细节理解题.根据Space Exploration Technologies部分的“SpaceX has been developing rocket technologies to enable Musk’s project.”可知，SpaceX一直在研究开发火箭技术，帮助Musk实现他的项目(目标)，故B项正确.4．What is Tesla Motors noted for?A．Its electric vehicles.B．Its photovoltaic products.C．Its service as a city tourist guide.D．Its business with other companies.A解析：细节理解题.根据Tesla Motors部分，尤其是该部分的第二句可知，Tesla Motors 是生产电动汽车的公司，故A项正确.BOphelia and the Mar v elous Boy by Karen FoxleeType：FantasyStoryline：When Ophelia moves to a strange city where it never stops snowing, she discovers a boy locked away for 75 years in a museum. She must help the boy before the Snow Queen freezes the world. Along the way, Ophelia learns how to believe in things she cannot see.Targeted readers：People who like fairy tales would enjoy this book.A Hundred Horses by Sarah LeanType: MysteryStoryline：The wooden horse Nell brings along during her visits to her aunt and cousins is stolen by a girl named Angel. As Nell finds out Angel’s true identity, a bond grows between them and a group of 99 horses. Word has it that the 100th horse is magical. But where is it? Nell doesn’t know, but Angel might know.Targeted readers：Kids who like animals and nature will be sure to find this book exciting.Ho w to Catch a Bogle by Catherine JinksType: FantasyStoryline：Birdie is an orphan who is good at trapping monsters with her singing voice. She is the only goblin(小妖精) hunter in the world. When kids go missing, it’s up to her to figure out why.Targeted readers：Anyone who is looking for monsters will take great pleasure in this book.I E v en Funnier: A Middle School Story by James Patterson and Chris GrabensteinType: FictionStoryline：After a car accident Jamie loses his family, and then he moves in with his aunt, uncle and his cousin Stevie, whose basic aim is to trick Jamie. But Jamie keeps having a positive attitude and running after his goals. He was recently honored the Funniest Kid Comic of New York State.Targeted readers：This book would be great for anyone who is fond of humorous books.【解题导语】本文是一篇应用文.文章介绍了四本书籍，提供了每本书的名称、作者、种类、故事情节和目标读者.5．Which writer tells a story about a girl saving a boy?A．Karen Foxlee.B．Sarah Lean.C．Catherine Jinks.D．James Patterson and Chris Grabenstein.A解析：细节理解题.根据文章对第一本书的简介，尤其是第二句“She must help the boy before the Snow Queen freezes the world.”可知，在冰雪女王冰冻世界之前Ophelia必须帮助那个男孩逃离，故选A.6．Nature lovers may take interest in________．A．Ophelia and the Mar v elous BoyB．A Hundred HorsesC．Ho w to Catch a BogleD．I E v en Funnier: A Middle School StoryB解析：细节理解题.根据第二本书对目标读者的描述“Kids who like animals and nature will be sure to find this book exciting.”可知，喜欢动物和自然的孩子一定会发现这本书令人兴奋，故第二本书A Hundred Horses符合要求，即B项正确.7．Who went through life challenges without losing heart?A．Ophelia.B．Nell.C．Stevie. D．Jamie.D解析：细节理解题.根据文章对第四本书的简介中的“But Jamie keeps having a positive attitude and running after his goals.”可知，Jamie在失去父母寄居在亲戚家时依旧保持积极的态度，追求自己的梦想，故选D项.8．In which section of a newspaper can we find such a passage?A．Fashion. B．Literature.C．Business. D．Local news.B解析：文章出处题.根据文章是对四本书的介绍可知，这篇文章可能来自报纸的文学版块，即B项正确.。
2019届高考英语第一轮单元考点复习SBIII Units 3～4The land down under & Green worldsbiii units 3～4the land down under & green world 澳大利亚考拉素材新挖掘考点1. govern vt. & vi. 统治(国家等)；控制；治理the constitutiongoverning six states stated that men were free and equal, explained theirbasic civil rights and described the new government.what about the lawsgoverning our investment and property in china?有关我们在中国投资和财产的法律如何？govern vt. & vi. 统治；治理govern vt. 控制；左右；抑制govern vt. 指导；支配；决定government n. 政府governor n. 统治者(1)who are the men that really _________(统治)in this country?(2)youshould govern your temper. (替换) ___________ (3)britain is governed by prime minister and the cabinet. (替换)___________(4)______________________________(我们的决定将受到控制)byamount of money we have to spend. (5)那位国王英明地统治国家。
Ⅰ阅读理解AJoseph Goldberger was a doctor for the United States Public Health Service and he was an advocate for scientific and social recognition of the links between poverty and disease. In 1914, Goldberger was asked by U．S. Surgeon General Rupert Blue to study a skin disease that was killing thousands of people in the South. The disease was pellagra(糙皮病)．Goldberger traveled to the state of Mississippi where many people suffered from pellagra. He studied the victims and their families. Most of the people lived a hard life. The doctor came to believe that the disease didn’t pass on from one to another, but was instead related to food. He received permission from the state governor to test this idea at a prison. Prisoners were offered pardons if they took part. One group of prisoners received their usual foods, mostly corn products.A second group ate meat, fresh vegetables and drank milk. Members of the first group developed pellagra. The second group did not.But some medical researchers refused to accept Goldberger’s idea. For the South, pellagra was more than simply a medical problem. There were other things, including Southern pride.So Goldberger had himself injected(注射) with blood from a person with pellagra. He also took liquid from the nose and throat of a pellagra patient and put them into his own nose and throat. He even swallowed pills that contained skin from pellagra patients. An assistant also took part in the experiments. So did Goldberger’s wife. None of them got sick.Joseph Goldberger died of cancer in 1929. He was fiftyfive years old. Several years later, researchers discovered the exact cause of pellagra：a lack of vitamin B3 known as niacin.【解题导语】本文是一篇记叙文。
