Unit 1 Welcome to junior high单元知识总结及重点易错专项训练 2026-2027学年教科版(五四学制)六年级英语上册

**基本信息** 聚焦Unit 1核心词汇、语法及交际用语，以十大易错考点为纲，通过基础-提升-拓展三层选择题训练，构建从词汇到语法再到应用的完整知识逻辑链，助力夯实基础与能力进阶。 **专项设计** |模块|题量/典例|题型特征|知识逻辑| |----|-----------|----------|----------| |十大易错考点|每考点9题（基础×3+提升×3+拓展×3）|以选择题为主，分层考查语法规则（be动词、代词等）与交际用语|从核心词汇（如junior, subject）、短语（welcome to, look forward to）到基础语法（代词、时态等），再到情境交际，形成"词汇-语法-应用"递进逻辑，贴合单元主题"初中生活"的语言能力培养需求|

教科版（五四学制）六年级上册 Unit 1 Welcome to junior high 单元知识总结及重点易错专项训练 ■ ■ ■ ■ ■ ■ ■ 说明：本练习紧扣最新教材精选 10 个重点易错考点，每个考点含基础题×3、提升题×3、拓展题×3，共 90 题。 一、重点单词 单词 词性 中文 junior adj. 初级的，年少的 welcome v. 欢迎 freshman n. 新生 subject n. 科目 schedule n. 时间表 introduce v. 介绍 yourself pron. 你自己 hobby n. 爱好 science n. 科学 history n. 历史 geography n. 地理 language n. 语言 activity n. 活动 club n. 俱乐部 practice v./n. 练习 improve v. 提高 challenge n./v. 挑战 manage v. 管理 organize v. 组织 experience n./v. 经历 environment n. 环境 experiment n. 实验 project n. 项目 research n. 研究 technology n. 科技 knowledge n. 知识 confident adj. 自信的 curious adj. 好奇的 independent adj. 独立的 responsible adj. 负责任的 creative adj. 有创造力的 energetic adj. 精力充沛的 friendly adj. 友好的 excited adj. 兴奋的 二、重点短语 短语 中文 welcome to 欢迎来到 look forward to 期待 take part in 参加 be interested in 对……感兴趣 get along with 与……相处 make friends 交朋友 learn about 了解 work hard at 努力学习 pay attention to 注意 be good at 擅长 be proud of 为……自豪 be responsible for 对……负责 take care of 照顾 grow up 长大 try one's best 尽力 in the future 将来 all over the world 全世界 on one's own 独自 as well as 也；和 deal with 处理 come up with 想出 set up 建立 give up 放弃 三、重点句型 英文句型 中文 Welcome to junior high! 欢迎来到初中！ I'm looking forward to meeting you. 我期待见到你。 What subject do you like best? 你最喜欢什么科目？ I'm good at English. 我擅长英语。 I enjoy reading books. 我喜欢读书。 Could you introduce yourself? 你能介绍一下自己吗？ I'm interested in science. 我对科学感兴趣。 We should take part in activities. 我们应该参加活动。 It's important to study hard. 努力学习很重要。 The more you practice, the better you get. 你练习越多，进步越大。 四、重点语法 1. be动词(am/is/are)与主语一致性 2. 人称代词主格与宾格用法 3. 形容词性/名词性物主代词 4. 一般现在时及第三人称单数变化 5. 指示代词this/that/these/those 6. 名词复数规则与不规则变化 7. like/enjoy/love+doing结构 8. 方位介词in/on/under/next to/between 9. 自我介绍与问候交际用语 10. 单元重点短语辨析与运用 🎯 十大易错考点一览 考点 内容 考点一 be动词(am/is/are)与主语一致性 考点二 人称代词主格与宾格 考点三 形容词性/名词性物主代词 考点四 一般现在时及第三人称单数变化 考点五 指示代词this/that/these/those 考点六 名词复数规则与不规则变化 考点七 like/enjoy/love+doing结构 考点八 方位介词in/on/under/next to/between 考点九 单元重点短语辨析 考点十 自我介绍与问候交际用语 考点一：be动词(am/is/are)与主语一致性 ◇ 基础题（选择题） ◇（ ）1. I ______ a new student in this school. am is are be ◇（ ）2. She ______ from Kunming. am is are be ◇（ ）3. They ______ in Class 3. am is are be ▷ 提升题（选择题） ▷（ ）1. Neither Lily nor Bella ______ good at math. are is am be ▷（ ）2. Each of the students ______ a new book. have has are is ▷（ ）3. My friends and I ______ excited about the trip. am is are was ★ 拓展题（选择题） ★（ ）1. The teacher, together with her students, ______ visiting the lab. are were is be ★（ ）2. There ______ some milk and two apples on the table. are is have has ★（ ）3. Zhang Hao as well as his classmates ______ hard at school. work works are working were working 考点二：人称代词主格与宾格 ◇ 基础题（选择题） ◇（ ）1. ______ am a student from Xiamen. I Me My Mine ◇（ ）2. Chen Wei is my friend. I often play with ______. he his him himself ◇（ ）3. Please give the book to ______. she her hers herself ▷ 提升题（选择题） ▷（ ）1. Between you and ______, he is a great teacher. I me my mine ▷（ ）2. They invited Olivia and ______ to the party. I me my mine ▷（ ）3. The teacher asked Jam and ______ a question. he him his himself ★ 拓展题（选择题） ★（ ）1. It was ______ who helped Lily with her homework. he him his himself ★（ ）2. We should believe in ______ and never give up. we us ourselves ourself ★（ ）3. The story made everyone ______ laugh. they them their themselves 考点三：形容词性/名词性物主代词 ◇ 基础题（选择题） ◇（ ）1. This is ______ book. That one is yours. I me my mine ◇（ ）2. — Is this pen yours? — No, it's ______. he him his he's ◇（ ）3. We love ______ school very much. we us our ours ▷ 提升题（选择题） ▷（ ）1. My bag is blue. What about ______? you your yours yourself ▷（ ）2. Bella forgot ______ homework at home. she her hers herself ▷（ ）3. The computer on the desk is ______. they them their theirs ★ 拓展题（选择题） ★（ ）1. ______ classroom is bigger than ours. Them Their Theirs They ★（ ）2. I can't find my keys. Can I use ______? you your yours yourself ★（ ）3. Zhang Hao and Zhou Kai are cleaning ______ room. they them their theirs 考点四：一般现在时及第三人称单数 ◇ 基础题（选择题） ◇（ ）1. He usually ______ to school by bus. go goes going gone ◇（ ）2. Lily ______ TV every evening. watch watches watching watched ◇（ ）3. They ______ sports after class. play plays playing played ▷ 提升题（选择题） ▷（ ）1. My mother ______ in a hospital in Wuhan. work works working worked ▷（ ）2. The earth ______ around the sun. move moves moved moving ▷（ ）3. Chen Wei never ______ up late on weekdays. get gets getting got ★ 拓展题（选择题） ★（ ）1. Physics ______ a difficult subject for some students. are is were be ★（ ）2. Everyone in our class ______ English. like likes liked liking ★（ ）3. Olivia ______ to music while doing homework. listen listens listened listening 考点五：指示代词this/that/these/those ◇ 基础题（选择题） ◇（ ）1. ______ is my new friend, Lily. This These Those That ◇（ ）2. ______ books over there are mine. This That These Those ◇（ ）3. — What's ______ over there? — It's a cat. this that these those ▷ 提升题（选择题） ▷（ ）1. ______ apples here are fresh. Would you like one? This That These Those ▷（ ）2. Who are ______ people standing at the door? this that these those ▷（ ）3. I don't like ______ kind of music. I prefer this one. this that these those ★ 拓展题（选择题） ★（ ）1. ______ is a photo of our school. Look at it carefully. This That These Those ★（ ）2. ______ were the days we spent in Kunming. I miss them. This That These Those ★（ ）3. Is ______ your backpack on the chair? this these those them 考点六：名词复数规则与不规则变化 ◇ 基础题（选择题） ◇（ ）1. There are many ______ in the school library. book books bookes bookies ◇（ ）2. We have two ______ in our family. child childs children childes ◇（ ）3. The ______ are eating grass on the hill. sheep sheeps ship sheepes ▷ 提升题（选择题） ▷（ ）1. How many ______ do you have? tooth toothes teeth teethes ▷（ ）2. There is some ______ on the plate. knife knifes knives knifees ▷（ ）3. My ______ are very strict but kind. parent parents parentes parenties ★ 拓展题（选择题） ★（ ）1. I bought three ______ at the supermarket. box boxs boxes boxies ★（ ）2. The ______ in the zoo are very cute. monkey monkeys monkeies monkies ★（ ）3. Chen Wei has two ______. One is in Jinan, the other in Qingdao. home homes homees homs 考点七：like/enjoy/love+doing结构 ◇ 基础题（选择题） ◇（ ）1. I enjoy ______ basketball with my friends. play to play playing played ◇（ ）2. Olivia loves ______ to music in her free time. listen listens listening to listen ◇（ ）3. They like ______ games after school. play playing to play played ▷ 提升题（选择题） ▷（ ）1. Jam is fond of ______ stamps. collect collects collecting to collect ▷（ ）2. Which do you prefer, ______ or swimming? run runs running to run ▷（ ）3. Bella doesn't mind ______ housework at home. do does doing to do ★ 拓展题（选择题） ★（ ）1. Zhang Hao is interested in ______ Chinese chess. play plays playing to play ★（ ）2. We are looking forward to ______ you soon. see seeing saw seen ★（ ）3. Lily suggested ______ to the library together. go going to go went 考点八：方位介词in/on/under/next to/between ◇ 基础题（选择题） ◇（ ）1. The book is ______ the desk. in on under between ◇（ ）2. There is a cat ______ the chair. in on under next to ◇（ ）3. The pencil is ______ the box. You can't see it. in on under between ▷ 提升题（选择题） ▷（ ）1. My school is ______ a park and a hospital. in on under between ▷（ ）2. There is a bank ______ our school. in on under next to ▷（ ）3. The ball is ______ the table and the chair. in on between next to ★ 拓展题（选择题） ★（ ）1. Olivia lives ______ Xiamen with her family. in on at under ★（ ）2. There is a map of China ______ the wall. in on under between ★（ ）3. The shoes are ______ the bed. You can find them easily. in on under between 考点九：单元重点短语辨析 ◇ 基础题（选择题） ◇（ ）1. I'm really ______ visiting the science museum. looking forward to looking at looking for looking after ◇（ ）2. Chen Wei is ______ collecting coins. interested in interested at interested on interested to ◇（ ）3. Let's ______ the school basketball team. take part in join join in attend ▷ 提升题（选择题） ▷（ ）1. She ______ her younger brother at home. takes care of takes care care of cares ▷（ ）2. We should ______ our studies and work hard. pay attention to pay attention attention to attention ▷（ ）3. Lily is very ______ her son's progress. proud of proud in proud on proud at ★ 拓展题（选择题） ★（ ）1. I ______ making mistakes when I speak English. am afraid of am afraid afraid of afraid ★（ ）2. They decided to ______ a club for science lovers. set up set out set off set down ★（ ）3. Zhou Kai ______ a good idea for the project. came up with came up came out came to 考点十：自我介绍与问候交际用语 ◇ 基础题（选择题） ◇（ ）1. — Nice to meet you! — ______ I'm fine. Nice to meet you, too! How are you? Goodbye! ◇（ ）2. — Hello, I'm Chen Wei. ______ — I'm Olivia. What's your name? How old are you? Where are you from? How do you do? ◇（ ）3. — How do you do? — ______ Fine, thanks. How do you do? I'm 13. See you. ▷ 提升题（选择题） ▷（ ）1. — Good morning, class! — ______ Good morning, teacher! Good afternoon! Good evening! Goodbye! ▷（ ）2. — Could you please introduce yourself? — ______ I'm 13 years old. I'm a student from Jinan. My name is Jam. I like sports. I'm fine. ▷（ ）3. — Welcome to our school! — ______ Thank you! You're welcome. That's OK. No problem. ★ 拓展题（选择题） ★（ ）1. — Let me introduce myself. I'm Lily. — ______ Nice to meet you, Lily. How are you, Lily? Where are you, Lily? Goodbye, Lily. ★（ ）2. — See you tomorrow! — ______ See you! Good morning! I'm sorry. Excuse me. ★（ ）3. — How are you doing? — ______ I'm doing my homework. I'm doing well, thanks. I'm a student. I'm 14 years old. 📝 参考答案（速查） 考点 答案（基础1-3 提升1-3 拓展1-3） 考点1 ABCBBCCBB 考点2 ACBBBBACB 考点3 CCCCBDBCC 考点4 BBABBBBBB 考点5 ADBCCBADA 考点6 BCACCBCBB 考点7 CCBCCCCBB 考点8 BCADDCABC 考点9 AABAAAAAA 考点10 BABACAAAB 📖 详细解析 考点1：be动词(am/is/are)与主语一致性 【基础题】 1.【答案】A 本题考be动词(am/is/are)与主语一致性。题干中"I ______ a new student in this school."，正确选项为A。 2.【答案】B 本题考be动词(am/is/are)与主语一致性。题干中"She ______ from Kunming."，正确选项为B。 3.【答案】C 本题考be动词(am/is/are)与主语一致性。题干中"They ______ in Class 3."，正确选项为C。 【提升题】 1.【答案】B 本题考be动词(am/is/are)与主语一致性。题干中"Neither Lily nor Bella ______ good at math."，正确选项为B。 2.【答案】B 本题考be动词(am/is/are)与主语一致性。题干中"Each of the students ______ a new book."，正确选项为B。 3.【答案】C 本题考be动词(am/is/are)与主语一致性。题干中"My friends and I ______ excited about the trip."，正确选项为C。 【拓展题】 1.【答案】C 本题考be动词(am/is/are)与主语一致性。题干中"The teacher, together with her students, ______ visiting the lab."，正确选项为C。 2.【答案】B 本题考be动词(am/is/are)与主语一致性。题干中"There ______ some milk and two apples on the table."，正确选项为B。 3.【答案】B 本题考be动词(am/is/are)与主语一致性。题干中"Zhang Hao as well as his classmates ______ hard at school."，正确选项为B。 考点2：人称代词主格与宾格 【基础题】 1.【答案】A 本题考人称代词主格与宾格。题干中"______ am a student from Xiamen."，正确选项为A。 2.【答案】C 本题考人称代词主格与宾格。题干中"Chen Wei is my friend. I often play with ______."，正确选项为C。 3.【答案】B 本题考人称代词主格与宾格。题干中"Please give the book to ______."，正确选项为B。 【提升题】 1.【答案】B 本题考人称代词主格与宾格。题干中"Between you and ______, he is a great teacher."，正确选项为B。 2.【答案】B 本题考人称代词主格与宾格。题干中"They invited Olivia and ______ to the party."，正确选项为B。 3.【答案】B 本题考人称代词主格与宾格。题干中"The teacher asked Jam and ______ a question."，正确选项为B。 【拓展题】 1.【答案】A 本题考人称代词主格与宾格。题干中"It was ______ who helped Lily with her homework."，正确选项为A。 2.【答案】C 本题考人称代词主格与宾格。题干中"We should believe in ______ and never give up."，正确选项为C。 3.【答案】B 本题考人称代词主格与宾格。题干中"The story made everyone ______ laugh."，正确选项为B。 考点3：形容词性/名词性物主代词 【基础题】 1.【答案】C 本题考形容词性/名词性物主代词。题干中"This is ______ book. That one is yours."，正确选项为C。 2.【答案】C 本题考形容词性/名词性物主代词。题干中"— Is this pen yours? — No, it's ______."，正确选项为C。 3.【答案】C 本题考形容词性/名词性物主代词。题干中"We love ______ school very much."，正确选项为C。 【提升题】 1.【答案】C 本题考形容词性/名词性物主代词。题干中"My bag is blue. What about ______?"，正确选项为C。 2.【答案】B 本题考形容词性/名词性物主代词。题干中"Bella forgot ______ homework at home."，正确选项为B。 3.【答案】D 本题考形容词性/名词性物主代词。题干中"The computer on the desk is ______."，正确选项为D。 【拓展题】 1.【答案】B 本题考形容词性/名词性物主代词。题干中"______ classroom is bigger than ours."，正确选项为B。 2.【答案】C 本题考形容词性/名词性物主代词。题干中"I can't find my keys. Can I use ______?"，正确选项为C。 3.【答案】C 本题考形容词性/名词性物主代词。题干中"Zhang Hao and Zhou Kai are cleaning ______ room."，正确选项为C。 考点4：一般现在时及第三人称单数 【基础题】 1.【答案】B 本题考一般现在时及第三人称单数。题干中"He usually ______ to school by bus."，正确选项为B。 2.【答案】B 本题考一般现在时及第三人称单数。题干中"Lily ______ TV every evening."，正确选项为B。 3.【答案】A 本题考一般现在时及第三人称单数。题干中"They ______ sports after class."，正确选项为A。 【提升题】 1.【答案】B 本题考一般现在时及第三人称单数。题干中"My mother ______ in a hospital in Wuhan."，正确选项为B。 2.【答案】B 本题考一般现在时及第三人称单数。题干中"The earth ______ around the sun."，正确选项为B。 3.【答案】B 本题考一般现在时及第三人称单数。题干中"Chen Wei never ______ up late on weekdays."，正确选项为B。 【拓展题】 1.【答案】B 本题考一般现在时及第三人称单数。题干中"Physics ______ a difficult subject for some students."，正确选项为B。 2.【答案】B 本题考一般现在时及第三人称单数。题干中"Everyone in our class ______ English."，正确选项为B。 3.【答案】B 本题考一般现在时及第三人称单数。题干中"Olivia ______ to music while doing homework."，正确选项为B。 考点5：指示代词this/that/these/those 【基础题】 1.【答案】A 本题考指示代词this/that/these/those。题干中"______ is my new friend, Lily."，正确选项为A。 2.【答案】D 本题考指示代词this/that/these/those。题干中"______ books over there are mine."，正确选项为D。 3.【答案】B 本题考指示代词this/that/these/those。题干中"— What's ______ over there? — It's a cat."，正确选项为B。 【提升题】 1.【答案】C 本题考指示代词this/that/these/those。题干中"______ apples here are fresh. Would you like one?"，正确选项为C。 2.【答案】C 本题考指示代词this/that/these/those。题干中"Who are ______ people standing at the door?"，正确选项为C。 3.【答案】B 本题考指示代词this/that/these/those。题干中"I don't like ______ kind of music. I prefer this one."，正确选项为B。 【拓展题】 1.【答案】A 本题考指示代词this/that/these/those。题干中"______ is a photo of our school. Look at it carefully."，正确选项为A。 2.【答案】D 本题考指示代词this/that/these/those。题干中"______ were the days we spent in Kunming. I miss them."，正确选项为D。 3.【答案】A 本题考指示代词this/that/these/those。题干中"Is ______ your backpack on the chair?"，正确选项为A。 考点6：名词复数规则与不规则变化 【基础题】 1.【答案】B 本题考名词复数规则与不规则变化。题干中"There are many ______ in the school library."，正确选项为B。 2.【答案】C 本题考名词复数规则与不规则变化。题干中"We have two ______ in our family."，正确选项为C。 3.【答案】A 本题考名词复数规则与不规则变化。题干中"The ______ are eating grass on the hill."，正确选项为A。 【提升题】 1.【答案】C 本题考名词复数规则与不规则变化。题干中"How many ______ do you have?"，正确选项为C。 2.【答案】C 本题考名词复数规则与不规则变化。题干中"There is some ______ on the plate."，正确选项为C。 3.【答案】B 本题考名词复数规则与不规则变化。题干中"My ______ are very strict but kind."，正确选项为B。 【拓展题】 1.【答案】C 本题考名词复数规则与不规则变化。题干中"I bought three ______ at the supermarket."，正确选项为C。 2.【答案】B 本题考名词复数规则与不规则变化。题干中"The ______ in the zoo are very cute."，正确选项为B。 3.【答案】B 本题考名词复数规则与不规则变化。题干中"Chen Wei has two ______. One is in Jinan, the other in Qingdao."，正确选项为B。 考点7：like/enjoy/love+doing结构 【基础题】 1.【答案】C 本题考like/enjoy/love+doing结构。题干中"I enjoy ______ basketball with my friends."，正确选项为C。 2.【答案】C 本题考like/enjoy/love+doing结构。题干中"Olivia loves ______ to music in her free time."，正确选项为C。 3.【答案】B 本题考like/enjoy/love+doing结构。题干中"They like ______ games after school."，正确选项为B。 【提升题】 1.【答案】C 本题考like/enjoy/love+doing结构。题干中"Jam is fond of ______ stamps."，正确选项为C。 2.【答案】C 本题考like/enjoy/love+doing结构。题干中"Which do you prefer, ______ or swimming?"，正确选项为C。 3.【答案】C 本题考like/enjoy/love+doing结构。题干中"Bella doesn't mind ______ housework at home."，正确选项为C。 【拓展题】 1.【答案】C 本题考like/enjoy/love+doing结构。题干中"Zhang Hao is interested in ______ Chinese chess."，正确选项为C。 2.【答案】B 本题考like/enjoy/love+doing结构。题干中"We are looking forward to ______ you soon."，正确选项为B。 3.【答案】B 本题考like/enjoy/love+doing结构。题干中"Lily suggested ______ to the library together."，正确选项为B。 考点8：方位介词in/on/under/next to/between 【基础题】 1.【答案】B 本题考方位介词in/on/under/next to/between。题干中"The book is ______ the desk."，正确选项为B。 2.【答案】C 本题考方位介词in/on/under/next to/between。题干中"There is a cat ______ the chair."，正确选项为C。 3.【答案】A 本题考方位介词in/on/under/next to/between。题干中"The pencil is ______ the box. You can't see it."，正确选项为A。 【提升题】 1.【答案】D 本题考方位介词in/on/under/next to/between。题干中"My school is ______ a park and a hospital."，正确选项为D。 2.【答案】D 本题考方位介词in/on/under/next to/between。题干中"There is a bank ______ our school."，正确选项为D。 3.【答案】C 本题考方位介词in/on/under/next to/between。题干中"The ball is ______ the table and the chair."，正确选项为C。 【拓展题】 1.【答案】A 本题考方位介词in/on/under/next to/between。题干中"Olivia lives ______ Xiamen with her family."，正确选项为A。 2.【答案】B 本题考方位介词in/on/under/next to/between。题干中"There is a map of China ______ the wall."，正确选项为B。 3.【答案】C 本题考方位介词in/on/under/next to/between。题干中"The shoes are ______ the bed. You can find them easily."，正确选项为C。 考点9：单元重点短语辨析 【基础题】 1.【答案】A 本题考单元重点短语辨析。题干中"I'm really ______ visiting the science museum."，正确选项为A。 2.【答案】A 本题考单元重点短语辨析。题干中"Chen Wei is ______ collecting coins."，正确选项为A。 3.【答案】B 本题考单元重点短语辨析。题干中"Let's ______ the school basketball team."，正确选项为B。 【提升题】 1.【答案】A 本题考单元重点短语辨析。题干中"She ______ her younger brother at home."，正确选项为A。 2.【答案】A 本题考单元重点短语辨析。题干中"We should ______ our studies and work hard."，正确选项为A。 3.【答案】A 本题考单元重点短语辨析。题干中"Lily is very ______ her son's progress."，正确选项为A。 【拓展题】 1.【答案】A 本题考单元重点短语辨析。题干中"I ______ making mistakes when I speak English."，正确选项为A。 2.【答案】A 本题考单元重点短语辨析。题干中"They decided to ______ a club for science lovers."，正确选项为A。 3.【答案】A 本题考单元重点短语辨析。题干中"Zhou Kai ______ a good idea for the project."，正确选项为A。 考点10：自我介绍与问候交际用语 【基础题】 1.【答案】B 本题考自我介绍与问候交际用语。题干中"— Nice to meet you! — ______"，正确选项为B。 2.【答案】A 本题考自我介绍与问候交际用语。题干中"— Hello, I'm Chen Wei. ______ — I'm Olivia."，正确选项为A。 3.【答案】B 本题考自我介绍与问候交际用语。题干中"— How do you do? — ______"，正确选项为B。 【提升题】 1.【答案】A 本题考自我介绍与问候交际用语。题干中"— Good morning, class! — ______"，正确选项为A。 2.【答案】C 本题考自我介绍与问候交际用语。题干中"— Could you please introduce yourself? — ______"，正确选项为C。 3.【答案】A 本题考自我介绍与问候交际用语。题干中"— Welcome to our school! — ______"，正确选项为A。 【拓展题】 1.【答案】A 本题考自我介绍与问候交际用语。题干中"— Let me introduce myself. I'm Lily. — ______"，正确选项为A。 2.【答案】A 本题考自我介绍与问候交际用语。题干中"— See you tomorrow! — ______"，正确选项为A。 3.【答案】B 本题考自我介绍与问候交际用语。题干中"— How are you doing? — ______"，正确选项为B。 学科网（北京）股份有限公司 $