Unit 2 Save the earth! 构词法-转化法（核心语法精练）英语新教材冀教版九年级下册

Unit 2 Save the earth!核心语法精练 （构词法-转化法） 目录 二、考点夯基 2 一、单项选择 2 二、单词拼写 3 三、完成句子 3 四、选词填空 3 一、语法选择 4 二、短文填空 5 构词法-转化法 一、单项选择 1．Ben said he had a ________. He ________ travel to a foreign country. A．planning, planned to B．plan, planned to C．planned, planned to D．plan, plan to 2．—Is the library _______  now? —No, it usually _______ at 9 a.m. A．opens; opens B．open; open C．open; opens D．opens; open 3．— What ______ you, dad? —I was ______ that the dog could do so many useful things for the disabled. A．surprised; surprised B．surprising; surprising C．surprised; surprising D．surprising; surprise 4．I want to ________ another two ________. A．book; books B．books; book C．book; book D．books; books 5．It often ________ a ________ of water. A．drop; drop B．drops; drops C．drops; drop D．drop; drops 6．The old lady has been __________ for two weeks and her __________ made her son lose himself. A．died；dead B．died；death C．dead；death D．dead；die 7．The shop _________with old people on weekends，but children _________in the interesting places. A．crowds；crowded B．crowded；crowds C．crowded；crowd D．is crowded；crowd 8．Mary ____________ the hat very much, because it's ____________ a cat. A．like;like B．like; likes C．likes;like D．likes; likes 9．To tell the ________, I don't agree with you. A．true B．truly C．truth D．truely 10．We are ___________ to hear that we will have a three-day off. A．please B．pleased C．pleasure D．pleasant 11．“How much do you　　　?”means“What’s your　　　?” A．weigh;weigh B．weigh;weight C．weight;weight D．weight;weigh 12．He got up ___________ yesterday morning. A．lately B．late C．latest D．latter 13．—Was there much ______in Nanjing last week?  —Yes. It snowed a lot. A．snows B．snowy C．snowed D．snow 14．He made his final __________  last winter and__________ from then on. A．appear; disappeared B．appearance; disappeared C．disappearance; appeared D．appearance; appeared 15．The man can make a __________ a horse. It __________ amazing. A．sound like; sounds B．sound like; listens C．sound; sounds like D．sound; sounds 二、单词拼写 1．My sister wants to be a ________ (cook) when she grows up. 2．Chopin’s music is the ________ (proud) of the whole country. 3．Many students ________ (development) a strong interest in science after doing fun experiments. 4．We walked on the ________ (sand) ground by the sea. 5．His ________ (join) in the music club made us very happy. 三、完成句子，根据汉语意思完成句子。 1．明天一定要穿运动鞋来学校。 _______ ________ ________ ________sports shoes to school tomorrow. 2．那场雨阻止了我们外出。 The rain_________us________ __________outside. 3．我们去帮忙灭火吧。 Let’s go to help_________ ___________ the fire. 4．骑自行车的时候要小心。 ________ __________when you ride a bike. 5．我想去超市买些小苏打。 I want to buy some________ __________in the supermarket. 四、选词填空 用方框中所给词或词组的适当形式填空。 south, minute, publish, even if, encourage, take place, health, go through, mention, important 1．Meat and fish are healthy food but hamburgers are food. 2．Tea is grown in the part of our country. 3．This company children’s books every year. 4．They don’t allow cars the city centre because it’s too crowded. 5．Susan’s voice still remained calm she was getting greatly annoyed. 6．Great changes in Huhhot since 2000. 7．It’s about ten walk from the school to the bookshop. 8．He to learn music and became a famous singer later. 9．Health is than wealth. 10．—Could I ask if you this to her till now? —Yes, but she refused to listen. 一、语法选择 There are four seasons in a year: spring, summer, autumn and winter. Each season brings different 1 and activities. Spring is a time of 2 . The weather gets warmer, and plants start to grow. People like to go on outings and 3 flowers in the park. Summer is 4 and sunny. It’s a great season for swimming, eating ice-cream and enjoying 5 days. But sometimes, there are heavy rains and storms. Autumn is a 6 season. The leaves turn yellow, red and brown, and fall to the ground. Farmers are busy 7 crops. It’s also a good time for hiking and having picnics. Winter is cold and 8 . Snow covers the ground in many places. Children love playing in the snow, 9 snowmen and going skiing. Each season is special in its own way. We should enjoy the beauty of each season and 10 the changes in nature. 1．A．colors B．weather C．sounds D．smells 2．A．ending B．sleeping C．birth D．death 3．A．watch B．look C．see D．notice 4．A．cool B．cold C．warm D．hot 5．A．rainy B．sunny C．cloudy D．windy 6．A．colorful B．colorless C．quiet D．noisy 7．A．growing B．harvesting C．planting D．watering 8．A．snowy B．rainy C．windy D．foggy 9．A．doing B．making C．building D．creating 10．A．hate B．enjoy C．fear D．miss 二、短文填空 阅读下面短文, 在空白处填入一个适当的词，或填入括号中所给单词的正确形式。 Tigers are beautiful animals. It’s hard to believe that there are only about one hundred South China tigers left on the earth—and few live in 1 wild. The largest animal in the world, the blue whale, 2 (live) in the oceans around the world. It feeds on one of the 3 (small) animals. Some people kill the whales. 4 a result, there may be only about 3,000 blue whales left now. The wild Bactrian camel is another animal 5 is in danger. It lives in Mongolia and the northwest of China. It is the only kind of camel in the world that has two humps (驼峰). There are only about 1,000 Bactrian camels left in the wild. Why is the situation getting so serious? People should think about the reasons 6 (care). There are lots of scientists doing important research to find out the best ways 7 (protect) animals. In order to make it 8 (easy) for the wild animals to live, we should protect their homes. We should also work hard to stop people from 9 (kill) them. If we can do these things 10 (good), there will be more wild animals in the world. 1 / 12 学科网（北京）股份有限公司 $ Unit 2 Save the earth!核心语法精练 （构词法-转化法） 目录 二、考点夯基 2 一、单项选择 2 二、单词拼写 5 三、完成句子 6 四、选词填空 7 一、语法选择 8 二、短文填空 10 构词法-转化法 一、单项选择 1．Ben said he had a ________. He ________ travel to a foreign country. A．planning, planned to B．plan, planned to C．planned, planned to D．plan, plan to 【答案】B 【详解】句意：本说他有一个_______。他________到一个外国去旅游。 考查名词和动词时态。plan作名词，意为计划；作动词时，后面跟动词不定式作宾语，意为“计划做某事”。根据第一句是一般过去时，可知第二句用一般过去时planned to，故选B。 2．—Is the library _______  now? —No, it usually _______ at 9 a.m. A．opens; opens B．open; open C．open; opens D．opens; open 【答案】C 【详解】句意：——现在图书馆开门了吗？——没有，它通常九点钟开门。 考查open作为动词和形容词的用法。open开，开着的；opens是动词open的第三人称单数形式；根据第一句中is是be动词，所以此处需要形容词，open可以作为形容词，表示“开着的”，所以第一空用open；第二句中主语it是第三人称单数形式，所以后接动词第三人称单数形式，所以第二空使用opens。故选C。 3．— What ______ you, dad? —I was ______ that the dog could do so many useful things for the disabled. A．surprised; surprised B．surprising; surprising C．surprised; surprising D．surprising; surprise 【答案】A 【详解】句意：——什么让你惊讶，爸爸？——我很惊讶这只狗能为残疾人做这么多有用的事情。 本题考查形容词和动词。surprise当动词讲时，表示使……惊讶；当名词讲时，表示惊讶；surprising是形容词，表示令人惊讶的。surprised是形容词，表示感到惊讶的。第一空作谓语，用动词，排除BD两项。第二空作为系动词was的表语，用形容词，表示我感到惊讶，用surprised。故选A。 4．I want to ________ another two ________. A．book; books B．books; book C．book; book D．books; books 【答案】A 【详解】句意：我还想要预定两本书。 考查构词法。book表示预定，是动词；表示书，是名词。want to do sth想要做某事，第一空用动词book。数词two修饰复数名词，用books，故选A。 5．It often ________ a ________ of water. A．drop; drop B．drops; drops C．drops; drop D．drop; drops 【答案】C 【详解】句意：它经常落下一滴水。 考查词义辨析。根据“It often...a...of water.”可知，第一个空为谓语，应是动词，drop作动词时，意为“落”，时态为一般现在时，主语为单三，动词也应用单三形式，故排除A和D；第二个空为名词，意为“滴”，是可数名词，a后面接名词单数。故选C。 6．The old lady has been __________ for two weeks and her __________ made her son lose himself. A．died；dead B．died；death C．dead；death D．dead；die 【答案】C 【详解】句意：那个老太太死了2周了，她的死亡让她的儿子很消沉。 be系动词，系动词，后接形容词，be dead死亡，延续性动词；die死，短暂性动词；for two weeks用延续性动词，完成时态；her她的，形容词性的物主代词，修饰名词，death死亡，名词；故选C。 7．The shop _________with old people on weekends，but children _________in the interesting places. A．crowds；crowded B．crowded；crowds C．crowded；crowd D．is crowded；crowd 【答案】D 【详解】句意：周末商店挤满老人，但是有趣的地方挤满了孩子。 本题考查动词和名词。crowd作动词讲，意为“挤满”；当名词讲，意为“人群”。be crowded with挤满。第一空缺少谓语，表示商店满是老人，用短语be crowded with。第二空作谓语，表示挤满，用动词，主语children是复数，谓语用复数形式。故选D。 8．Mary ____________ the hat very much, because it's ____________ a cat. A．like;like B．like; likes C．likes;like D．likes; likes 【答案】C 【详解】句意：玛丽非常喜欢那顶帽子，因为它想一只猫。 本题考查动词。like表示“像”，作介词，be like像；表示“喜欢”，是动词。第一空作谓语，故用动词，主语Mary是第三人称单数，故谓语用第三人称单数likes。第二空根据is可知，此处用be like，故选C。 9．To tell the ________, I don't agree with you. A．true B．truly C．truth D．truely 【答案】C 【详解】句意：说实话，我不认同你（的观点）。 考查固定词组。A. true意为“真正的”，形容词；B. truly意为“真正地”，副词； C. truth 意为“事实、真相、实情”，固定词组：to tell the truth，意为“说实话”，常用作插入语。D项是错误项，true的副词形式应为：truly。故选C。 10．We are ___________ to hear that we will have a three-day off. A．please B．pleased C．pleasure D．pleasant 【答案】B 【详解】句意：听说我们要休息三天，我们很高兴。 考查形容词辨析。please愉快，动词；pleased高兴的，形容人；pleasure快乐，名词；pleasant令人愉快的，形容物。本句缺表语形容词，主语we是人；根据句意语境，可知We are pleased符合句意，故选B。 11．“How much do you　　　?”means“What’s your　　　?” A．weigh;weigh B．weigh;weight C．weight;weight D．weight;weigh 【答案】B 【详解】句意：“你有多重？意思是“你的体重是多少？”考查词性转换。weigh：重，称重量，动词；weight：重量，分量，名词。第一句缺少谓语动词，可知填weigh；第二句your是形容词性的物主代词，形容词性的物主代词修饰名词，可知后面是名词，可知填weight；选B。 12．He got up ___________ yesterday morning. A．lately B．late C．latest D．latter 【答案】B 【详解】句意：他昨天早上起晚了。本题中的“晚”应是个副词，修饰“起床”，late本身就可以用作副词，lately意为“最近”，latest意为“最晚或最近的”，latter意为“后面的”。故答案选B。 13．—Was there much ______in Nanjing last week?  —Yes. It snowed a lot. A．snows B．snowy C．snowed D．snow 【答案】D 【详解】句意：——南京上星期雪多吗？——是的，下了很多雪。 考查snow。snow名词，雪；动词，下雪；snowy形容词，多雪的；much后用不可数名词，故选D。 14．He made his final __________  last winter and__________ from then on. A．appear; disappeared B．appearance; disappeared C．disappearance; appeared D．appearance; appeared 【答案】B 【详解】试题分析: 句意：去年冬天他最后一次现身，从那以后就消失了。appear 出现，名词形式为appearance；disappear消失，名词形式为disappearance; from then on 从那时起; final最后的，修饰名词；根据语境可知是从最后一次出现后一直消失，故选B。 考点：考查词性转换 15．The man can make a __________ a horse. It __________ amazing. A．sound like; sounds B．sound like; listens C．sound; sounds like D．sound; sounds 【答案】A 【详解】试题分析：句意：这个人能够像马发出一种声音。它听起来令人惊讶。此题考查sound是名词声音，还可以当动词，听起来。根据句意，应选A。 考点：考查名词和动词。 二、单词拼写 1．My sister wants to be a ________ (cook) when she grows up. 【答案】cook 【详解】句意：我的妹妹长大后想成为一名厨师。cook“烹饪”，为动词，也可作名词“厨师”。此处位于不定冠词a之后，需要名词作表语，表示职业“厨师”，故用其名词原形cook。 2．Chopin’s music is the ________ (proud) of the whole country. 【答案】pride 【详解】句意：肖邦的音乐是整个国家的骄傲。定冠词the后接名词，proud的名词形式是pride，意为“骄傲”。 3．Many students ________ (development) a strong interest in science after doing fun experiments. 【答案】developed 【详解】句意：许多学生在做过有趣的实验之后，对科学产生了浓厚的兴趣。句中“after doing fun experiments”为过去发生的事件，提示动作发生在过去，应用一般过去时。development是名词，要先变为动词develop，develop的过去式直接加‑ed，故填developed。 4．We walked on the ________ (sand) ground by the sea. 【答案】sandy 【详解】句意：我们走在海边的沙地上。名词ground前需要形容词作定语，sand是名词，形容词形式为sandy。 5．His ________ (join) in the music club made us very happy. 【答案】joining 【详解】句意：他加入音乐俱乐部这件事让我们非常开心。形容词性物主代词His后需要动名词作句子主语，join的动名词形式为joining，故填joining。 三、完成句子，根据汉语意思完成句子。 1．明天一定要穿运动鞋来学校。 _______ ________ ________ ________sports shoes to school tomorrow. 2．那场雨阻止了我们外出。 The rain_________us________ __________outside. 3．我们去帮忙灭火吧。 Let’s go to help_________ ___________ the fire. 4．骑自行车的时候要小心。 ________ __________when you ride a bike. 5．我想去超市买些小苏打。 I want to buy some________ __________in the supermarket. 【答案】1． Be sure to wear   2． prevented from going 3． put out    4． Be careful    5． baking soda 【解析】1．根据题干中“一定要穿”没有完成翻译，此句是祈使句，要用动词原形+其他。由此空“一定要穿”的意思，故答案为(1). Be   (2). sure    (3). to    (4). wear 。 2．由prevent sb. from doing sth. 阻止某人做某事。根据语境可知事情发生在过去，故用动词的过去式。故答案为(1). prevented    (2). from    (3). going 。 3．根据句意可知，此句是祈使句。此空是“扑灭”的意思， 由help do sth. 帮助做某事，故答案为(1). put   (2).out。 4．根据句意可知，此句是when引导的时间状语从句，主句是祈使句，要用动词原形+其他，此空是“小心”的意思，故答案为1). Be  (2). careful 。 5．此句是一般现在时态的肯定句。结合句意，此空是“小苏打”的意思，some后接不可数名词baking soda，故答案为(1). baking (2). soda。 四、选词填空 用方框中所给词或词组的适当形式填空。 south, minute, publish, even if, encourage, take place, health, go through, mention, important 1．Meat and fish are healthy food but hamburgers are food. 2．Tea is grown in the part of our country. 3．This company children’s books every year. 4．They don’t allow cars the city centre because it’s too crowded. 5．Susan’s voice still remained calm she was getting greatly annoyed. 6．Great changes in Huhhot since 2000. 7．It’s about ten walk from the school to the bookshop. 8．He to learn music and became a famous singer later. 9．Health is than wealth. 10．—Could I ask if you this to her till now? —Yes, but she refused to listen. 【答案】 1．unhealthy 2．southern 3．publishes 4．to go through 5．even if 6．have taken place 7．minutes’ 8．was encouraged 9．more important 10．have mentioned 【详解】1．句意：肉和鱼是健康的食物，但是汉堡是不健康的食物。 根据“Meat and fish are healthy food”和“but”可知，汉堡是不健康的食物。故填unhealthy。 2．句意：茶种在我国南方地区。根据“in the … part of our country”可知，此空应填形容词，且填方向。故填southern。 3．句意：这家公司每年都要印刷儿童书籍。根据“children’s books”可知，是印刷儿童书籍；根据“every year”和“this company”可知使用一般现在时第三人称单数。故填publishes。 4．句意：他们不允许汽车穿过市中心，因为市中心太拥挤了。根据“because it's too crowded”可知，不允许汽车通过，应该使用“go through”；根据“allow sb./sth. to do sth.”可知，应该使用动词不定式。故填to go through。 5．句意：苏珊的声音仍然很平静，即使她很生气。根据上下句表示一种让步关系，表示“即使”。故填even if。 6．句意：呼和浩特市自2000年以来发生了巨大变化。根据“Great changes”可知，应该使用“take place”；根据“since 2000”可知，应该使用现在完成时have/has done的结构，主语changes是复数形式，助动词用have。故填have taken place。 7．句意：从学校步行到书店大约十分钟的路程。根据“from the school to the bookshop”可知，应该表示距离；ten后接复数名词，此空修饰名词“walk”要用名词所有格。故填minutes’。 8．句意：他被鼓励学习音乐，后来成为一名著名的歌手。根据“became a famous singer later”可知，这是鼓励的结果；根据“became”可知，应该使用一般过去时；根据“He”和“encourage”之间的关系可知，应该使用被动语态。故填was encouraged。 9．句意：健康比财富更加重要。根据“than”可知，应该使用比较级。根据常识可知，健康比财富更重要，故填more important。 10．句意：——我能问问你到现在为止有没有跟她提起过这件事吗？——是的，但她拒绝听。根据“she refused to listen”和“till now”可知，已经提及此事，并且使用现在完成时。故填have mentioned。 一、语法选择 There are four seasons in a year: spring, summer, autumn and winter. Each season brings different 1 and activities. Spring is a time of 2 . The weather gets warmer, and plants start to grow. People like to go on outings and 3 flowers in the park. Summer is 4 and sunny. It’s a great season for swimming, eating ice-cream and enjoying 5 days. But sometimes, there are heavy rains and storms. Autumn is a 6 season. The leaves turn yellow, red and brown, and fall to the ground. Farmers are busy 7 crops. It’s also a good time for hiking and having picnics. Winter is cold and 8 . Snow covers the ground in many places. Children love playing in the snow, 9 snowmen and going skiing. Each season is special in its own way. We should enjoy the beauty of each season and 10 the changes in nature. 1．A．colors B．weather C．sounds D．smells 2．A．ending B．sleeping C．birth D．death 3．A．watch B．look C．see D．notice 4．A．cool B．cold C．warm D．hot 5．A．rainy B．sunny C．cloudy D．windy 6．A．colorful B．colorless C．quiet D．noisy 7．A．growing B．harvesting C．planting D．watering 8．A．snowy B．rainy C．windy D．foggy 9．A．doing B．making C．building D．creating 10．A．hate B．enjoy C．fear D．miss 【答案】 1．B 2．C 3．A 4．D 5．B 6．A 7．B 8．A 9．B 10．B 【导语】本文主要介绍了一年四季的气候特征、自然变化及人们在不同季节的典型活动，倡导人们享受自然之美。 【详解】1．句意：每个季节带来不同的天气和活动。 后文分别介绍了四个季节不同的天气特征和对应活动“Spring is a time of…Summer…Autumn…Winter”，weather（天气）是四个季节最核心的差异要素之一，其余选项都不能概括四季共有的典型差异。 2． 句意：春天是万物诞生的时节。 根据后文“plants start to grow”，可知象征新生，birth在这里引申为万物复苏的开端，其余选项都不符合春天的特点。 3．句意：人们喜欢郊游和在公园观赏花朵。 这里指人们在公园观赏花卉，watch有“观赏、专注欣赏”的含义，符合赏花的搭配；look是不及物动词不能直接接宾语，see侧重“看见”的结果，notice侧重“注意到”，都不符合语境。 4．句意：夏天炎热且阳光明媚。 夏天的典型气候特征是炎热，hot符合常识，cool是秋天的特点，cold是冬天的特点，warm是春天的特点。 5．句意：这是一个游泳、吃冰淇淋和享受阳光明媚的好季节。 前文说夏天晴朗，是游泳、吃冰淇淋的好时节，对应享受晴好的日子，sunny（晴朗的），也和后文转折说“但有时会有暴雨风暴”形成逻辑呼应。，其余选项都和这类惬意的夏日活动不匹配。 6． 句意：秋天是一个多彩的季节。 后文提到秋天的叶子会变成黄、红、棕等多种颜色“The leaves turn yellow, red and brown, and fall to the ground”，说明秋天是五彩斑斓的，colorful完全对应这个描述，其他选项不符合这一描述。 7．句意：农民忙着收割庄稼。 秋天是收获的季节，农民忙着收割庄稼，harvest（收割）符合秋季农事特征，其他选项活动都不是秋季的典型农活。 8．句意：冬天寒冷且多雪。 后文提到地面被雪覆盖“Snow covers the ground in many places.”，对应冬天多雪的特征，snowy符合语境。 9．句意：孩子们喜欢在雪地里玩，堆雪人和滑雪。 固定搭配make snowmen表示“堆雪人”。 10．句意：我们应该欣赏每个季节的美丽并享受自然的变化。 前文说每个季节都很特别，我们应该欣赏每个季节的美，顺承逻辑就是享受大自然的变化，enjoy符合全文积极的基调。hate憎恨；fear害怕；miss怀念，不符合全文积极的主旨。 二、短文填空 阅读下面短文, 在空白处填入一个适当的词，或填入括号中所给单词的正确形式。 Tigers are beautiful animals. It’s hard to believe that there are only about one hundred South China tigers left on the earth—and few live in 1 wild. The largest animal in the world, the blue whale, 2 (live) in the oceans around the world. It feeds on one of the 3 (small) animals. Some people kill the whales. 4 a result, there may be only about 3,000 blue whales left now. The wild Bactrian camel is another animal 5 is in danger. It lives in Mongolia and the northwest of China. It is the only kind of camel in the world that has two humps (驼峰). There are only about 1,000 Bactrian camels left in the wild. Why is the situation getting so serious? People should think about the reasons 6 (care). There are lots of scientists doing important research to find out the best ways 7 (protect) animals. In order to make it 8 (easy) for the wild animals to live, we should protect their homes. We should also work hard to stop people from 9 (kill) them. If we can do these things 10 (good), there will be more wild animals in the world. 【答案】 1．the 2．lives 3．smallest 4．As 5．that/which 6．carefully 7．to protect 8．easier 9．killing 10．well 【导语】本文是一篇关于濒危野生动物保护的说明文。 【详解】1．句意：很难相信目前全球仅存约100只华南虎，且几乎没有华南虎生活在野外。固定搭配in the wild，意为“在野外”，是固定表达，故填the。 2．句意：世界上最大的动物——蓝鲸，生活在全球的各大洋中。句子主语是the blue whale（蓝鲸），此处指代蓝鲸这一物种，视作单数概念，且全文为一般现在时，谓语动词要用第三人称单数形式lives。 3．句意：蓝鲸以（海洋里）最微小的生物之一为食。固定结构one of + the + 形容词最高级 + 可数名词复数，意为“最……的……之一”，此处需要用small的最高级形式smallest。 4．句意：结果，现在现存的蓝鲸可能仅3000头左右。as a result是固定短语，意为“结果、因此”，用于引出前文动作导致的后果，单词位于句首首字母需大写。 5．句意：野生双峰驼是另一种濒临灭绝的动物。此处为定语从句，先行词是animal（动物，指代事物），需用关系代词that/which，在从句中作主语。 6．句意：人们应当认真地思考这些原因。此处修饰动词短语think about（思考），需要用副词形式，因此care对应的副词变形为carefully。 7．句意：有许多科学家正在开展重要研究，目的是找出保护动物的最佳方法。protect“保护”为动词，固定结构the way/ways to do sth. 意为“做某事的方法”，此处用不定式作后置定语，修饰名词ways，故填to protect。 8．句意：为了让野生动物的生存变得更加容易，我们应当保护它们的家园。后文暗含“（和不保护栖息地相比）让野生动物生存得更轻松”的比较含义，因此需要用形容词easy的比较级形式easier，作宾语补足语。 9．句意：我们也应该努力阻止人们猎杀它们。固定结构stop sb. from doing sth. 意为“阻止某人做某事”，介词from后面需要接动名词形式，动词kill的动名词为killing。 10．句意：如果我们能把这些事做好，世界上就会有更多的野生动物。此处修饰动作do these things（做这些事），需要用副词，因此形容词good对应的副词变形为well。 1 / 12 学科网（北京）股份有限公司 $