小学英语四年级上册Unit 1 My classroom 单元测试卷及答案-人教PEP版英语

Unit1 测试卷时间：60分钟满分：100分听力部分（40分）一、听录音，选出与所听内容相符的图片。

（5分）( ) 1. A. B. C.( ) 2. A. B. C.( ) 3. A. B. C.( ) 4. A. B. C.( ) 5. A. B. C.二、听录音，判断下列句子与所听内容是（√）否（×）一致。

（5分）( ) 1. We have a new classroom.( ) 2. The wall is orange.( ) 3. The computer is on the desk.( ) 4. The picture is near the window.( ) 5. Let’s clean the blackboard!三、听录音，按所听顺序用1-5给下列图片排序。

（10分）( ) ( ) ( ) ( ) ( )四、听录音，为你所听到的句子选择正确的答语。

（10分）( ) 1. A. It’s on the floor. B. It’s green. C. Yes, it is.( ) 2. A. It’s so big. B. I like it.C. Six lights and a blackboard.( ) 3. A. Thank you. B. Excuse me. C. You’re welcome. ( ) 4. A. Goodbye. B. OK. C. It’s long.( ) 5. A. No, it isn’t. B. It’s on the desk. C. It’s a computer.五、听录音，根据所听内容选词填空（只填序号）。

（10分）Hello! I’m Mike. We have a new 1. ________. It’s so big and clean. Two 2.________, six 3. ________, many 4. ________ and chairs in it. Look, my seat（座位）is near the 5. _________.笔试部分（60分）六、选出每组中画线部分读音不同的一项。

四年级英语上册第一单元测试题一．选出以下各组词汇中不同类的一项，将其序号填入题前括号内。

(10分）( ) 1. A. classroom B. light C. fan( ) 2. A. clean B. open C. close( ) 3. A. desk B. computer C. chair( ) 4. A. cake B. this C. that( ) 5. A. wall B. floor C. class二．看图，补全句子。

(10分）()1.This is the new.A.classroomB.teacher’s deskC.blackboard()2.Let’s clean the.A.floorB.wallC.windows()3.The floor is.A.g reenB.yellowC.red()4.— Where is the fan?— It’s the wall.A.nearB.onC.in()5. Let me clean the .A. classroomB. blackboardC. floor三．单项选择。

(10分）() 1. Let’s the classroom.A. helpB. cleanC. close() 2. Let clean the blackboard.A. IB. myC. me() 3. — is the green chair?—It’s near the window.A.WhereB. WhatC. How() 4. — in the classroom?—Many desks and chairs.A.Where’sB. What’sC.What() 5. The pictures________yellow.A.isB. areC. am 四．选择单词，补全句子。

(10分）1.The is red.2.We a big classroom.3. me clean the windows.4.— Where the teacher's desk?— It is on the floor.5.Look! The desks green.五．情景交际。

人教pep版四年级上册英语第一单元Unit1《My Classroom》单元测试卷（含听力材料及答案）时间：40分钟满分：100分第一部分听力(40分)一、听句子，选出你所听到的单词。

(10分)( )1. A. cat B. cake C. Kate( )2. A. near B. new C. under( )3. A. what B. where C. who( )4. A. window B. door C. floor( )5. A. fan B. face C. wall二、听句子，圈出与所听内容相符的图片。

(10分)1. A. B.2. A. B.3. A. B.4. A. B.5. A. B.三、听句子，选择正确的答语。

(10分)( )1. A. OK. B. Thank you.( )2. A. It’s blue. B. It’s near the blackboard.( )3. A. It’s black. B. It’s on the desk.( )4. A. It’s small. B. Many desks and chairs.( )5. A. Really? B. Open the door.四、听短文，选出图中物品对应的颜色，并将其序号填到横线上。

(10分)A. blueB. orangeC. yellowD. greenE. brown第二部分笔试(60分)五、判断下列单词画线部分发音是(S)否(D)相同。

(10分)( )1. make cake( )2. name Jane( )3. have date( )4. dad cap( )5. face map六、单项选择。

(10分)( )1. Let ________ clean the fan.A. IB. meC. my( )2. We have ________ new classroom.A. aB. anC. the( )3. I can see many ________ in the classroom.A. doorB. picturesC. light( )4. The window is ________ the door.A. underB. onC. near( )5. It’s black. It’s long and big. It’s on the wall. The teacher writes (写) on it. It’s a ________.A. computerB. windowC. blackboard七、根据图片提示，判断句子或对话正(T)误(F)。

四年级英语上册Unitl My classroom单元测试人教版（PEP）（含答案及解析）一、单选题（共10题）1. —Who is that? —She's my sister.A.boyB.girlC.man2. —Excuse me, Jack. Where is the bus?A.In the treeB.On the treeC.Near the tree3.—Let's clean the classroom.A.OK!B.Goodbye!C.Thank you.4.—Where's my ruler?A.It's so big.B.It's in the desk.C.It's a bag.5.一Let me help you.A.Really?B.Thank you.C.All right.6.—Sarah, we have a new classroom.一Let's go and have a look.A.Really?B.Thank you.C.All right.7.—Where is my picture?A.It's near the window.B.It's a bee.C.It's so big.8.the blackboard, please.A.SweepB.CleanC.Open9.—is my ruler?— It's on the desk.A.WhatB.What colourC.Where10.—is your pencil?— It's on the desk.A.WhatB.WhereC.How二、填空题(共2题)11.判断下面每组单词画线部分读音是否相同。

① A.have B. cake C. cat② B. face C. make③ A.hate B. date C. map④ A.hat B. cap C. dad⑤ A.fan B. are C. face12.为下列句子选择正确的图片。

人教PEP版四年级英语上册第一单元提分训练卷一、单选题1．—Let me help you. （）— .A．Thanks B．No C．OK2．_________clean the classroom（）A．Let we B．Let’s me C．Let’s3．I ______ my classroom. ( )A．am B．like C．have4．The desks and chairs ______ red and orange. ( )A．is B．am C．are5．—What are they? （）—They are .A．computers B．light C．teacher’s desk 6．— is my book? （）—It’s in the desk.A．What B．Who C．Where7．The pictures on the wall. （）A．am B．is C．are8．Let go and see. （）A．us B．we C．I9．—Let's put up the pictures. （）—________.A．Goodbye B．Good idea C．Good morning10．What's in the classroom?( )A．I can see a pencil. B．I can see many desks.二、选词/短语填空1．Look! This ________ （is, are） my new classroom.2．The floor is green. The ________ （teacher, teacher’s） desk is yellow.3．Let ________ （I, me） clean the blackboard.4．Three ________ （desk, desks） are yellow.5．We ________ （have, has） a new teacher.三、英译汉。

（人教PEP）四年级上英语Unit1myclassroom单元测试及答案4班别：______________ 姓名：______________ 成绩：________________听力部分（满分60分）一、Listen and choose. 听音，选择。

每小题读两遍。

（10分）( ) 1. A. cat B. cake ( ) 2. A. rat B. rate ( ) 3. A. date B. dad ( ) 4. A. hat B. hate ( ) 5. A. make B. map ( ) 6. A. face B. fat ( ) 7. A. lack B. lake ( ) 8. A. bag B. bake ( ) 9. A. take B. tap ( )10. A. pat B. pate二、Listen and choose. 听录音，选出与录音内容相符合的一项，并将其字母序号填写在题前的括号里。

每小题读两遍。

（10分）（）1. A. classroom B. bedroom C. bathroom（）2. A. come B. C. crayon（）3. A. wall B. walk C. window（）4. A. light B. night C. nine（）5. A. duck B. ball C. door（）6. A. picture B. pupil C. pencil（）7. A. four B. floor C. foot（）8. A. teacher’s desk B. student’s desk C. many desks（）9. A. Let me clean the classroom.B. Let me clean the windows.C. Let me clean the blackboard.（）10. A. It’s in the teacher’s desk.B. It’s under the teacher’s desk.C. It’s near the teacher’s desk.三、Listen and choose.听录音内容，选择正确答案。

⼩学英语四年级上册Unit1Myclassroom单元测试卷及答案-⼈教PEP版英语⼈教PEP版英语四年级上册Unit 1 My classroom 单元测试卷⼀、选择题（题型注释）1.A. help B. wall C. floor2.A. computer B. TV C. picture3.A. near B. really C. under4.A. colour B. green C. yellow5.A. clean B. sweep C. desk6.A. what B. where C. there7.A. my B. me C. your8.A. kite B. bee C. fish9.There's a bee_______the blackboard. ( )A. onB. inC. after10.Let's______the classroom! ( )A. cleanB. cleansC. cleaning11.This is_____new pen. ( )A. IB. meC. my12.---_______is the picture? ( )---It is on the floorA. WhatB. WhereC. Who13.---_______is in the classroom? ( )---Many desks and chairs.A. HowB. WhereC. What⼆、匹配题英汉配对。

A. 电灯B. 教室C. 地板D. 门E. ⿊板F. 讲台G. 风扇H. 窗户I. 计算机J. 打扫K.墙壁L. 图画14.floor （_______）15.door （_______）16.light （_______）17.blackboard （_______）18.classroom （_______）19.teacher’s desk（_______）/doc/0c527493e418964bcf84b9d528ea81c759f52edf.html puter （_______）21.wall （_______）22.fan （_______）23.clean （_______）24.window （_______）25.picture （_______）给下列句⼦选择相应的图⽚。

Unit 1 My classroom满分:100分时间:60分钟得分:听力部分一、听录音,给图片排序。

(10分)( ) ( ) ( ) ( ) ( ) 二、听录音,判断单词与内容是(T)否(F)相符。

(10分)1. 2. 3. 4. 5.三、听录音,选择单词,补全句子。

(10分)( )1.This is the new .A.classroomB.teacher’s deskC.blackboard( )2.Let’s clean the .A.floorB.wallC.windows( )3.The window is .A.greenB.yellowC.red( )4.— Where is it?—It’s the door.A.nearB.underC.in( )5. clean the classroom.A.Let’sB.Let meC.Let him笔试部分classroom fan computer blackboard door1.This is a .2.My is big.3.The is new.4.Clean the .5.The is yellow.1.The is yellow.2.We a big classroom.3. me clean the teacher’s desk.4.— Where the bee?— It is on the wall.5.Look! The desks green.七、给下列句子选择相应的图片。

(8分)A. B. C. D.( )1.Put up the picture.( )2.Let me clean the blackboard.( )3.The boy is on the floor.( )4.The book is on the desk.八、情景交际。

(10分)( )1.别人帮助你之后,你应该对他/她说:A.Let me help you.B.Thank you.C.OK.( )2.你想建议大家一起打扫教室,应该说:A.Let’s clean the windows.B.Let’s go to the classroom.C.Let’s clean the classroom.( )3.你想问窗户在哪儿,应该说:A.Where is the door?B.Where is the window?C.Where is the light?( )4.你想告诉大家“就在书桌旁边”,应该说:A.I t’s a desk.B.It’s near the desk.C.It’s under the desk.( )5.你想知道教室里有什么,应该说:A.What’s in the classroom?B.Is it in the classroom?C.Where is the classroom?九、阅读短文,完成下列各题。

Unit 1 My classroom满分:100分时间:60分钟得分:听力部分一、听录音,给图片排序。

(10分)( ) ( ) ( ) ( ) ( ) 二、听录音,判断单词与内容是(T)否(F)相符。

(10分)1. 2. 3. 4. 5.三、听录音,选择单词,补全句子。

(10分)( )1.This is the new .A.classroomB.teacher’s deskC.blackboard( )2.Let’s clean the .A.floorB.wallC.windows( )3.The window is .A.greenB.yellowC.red( )4.—Where is it?—It’s the door.H.door G.picture F.window E.floorC.lightD.blackboard B.wall A.deskclassroomfan computer blackboard doorA.nearB.underC.in ( )5.clean the classroom. A.Let’s B.Let meC.Let him笔试部分四、看图,给物品选择相应的单词。

(16分)五、根据图片,选择单词,补全句子。

(10分)1.This is a .2.My is big.3.The is new.4.Clean the .5.The is yellow.六、选择单词,补全句子。

(10分)is are door Let have1.T he is yellow.2.W e a big classroom.3.me clean the teacher’s desk.4.—Where the bee?—It is on the wall.5.L ook! The desks green.七、给下列句子选择相应的图片。

(8分)A. B. C. D.( )1.Put up the picture.( )2.Let me clean the blackboard.( )3.The boy is on the floor.( )4.The book is on the desk.八、情景交际。

Unit 1 My classroom 单元测试姓名：班级：座号：一、单选题（共10题；共20分）1.—_______.—OK.A. Let's clean the classroom.B. Let me clean the classroom.2.This girl is my________.A. sonB. daughter3.当卡卡龙想知道小天的教室里有什么的时候，卡卡龙应说：________A. What's in the classroom?B. What's at the classroom?4.______ go and see.( )A. LetB. Let isC. Let us5.根据图片，选出正确选项。

（）A. It's a kite.B. It's a fish.6.________ the blackboard, please.A. SweepB. CleanC. Open7.—This is the new classroom.—_______.A. Really?B. Oh, the door is orange.C. Let me clean the windows.8.教室那么大。

（）A. I like my class.B. The classroom is so big.9.你想说我们都是好朋友，你会说：（）A. She's my good friend.B. We are good friends.10.根据图片，选出正确选项。

（）A. Open the book.B. Open the umbrella.二、填空题（共3题；共15分）1.选出不同类别的单词。

(________)1. A. classroom B. girl C. bedroom(________)2. A. door B. chair C. dog(________)3. A. see B. go C. where(________)4. A. light B. blackboard C. fans(________)5. A. where B. what C. let2.选出与单词对应的图片。

Unit 1 My classroom 单元测试一、Listen and write.（听录音，写单词。

）1. ________ desks and chairs2. ________ the door3. ________ and see4. ________ ________ the light5. ________ my classroom二、Look, fill and match.（看图，将单词补充完整，并连线。

）1. __an2. w__ll3. l__ght4. w__ndow5. d__ __rA B C D E三、Read and choose.（读句子，选择正确答案。

）（）1. —________?—One blackboard, one TV, many desks and chairs.A. Where is the classroomB. What’s in the classroomC. What in the classroom（）2. —________ is your picture?—It’s near the window.A. WhatB. WhereC. Where’s（）3. —________ is the chair?—It’s blue.A. WhatB. What colourC. What’s colour（）4. Let’s ________ the window.A. closeB. helpC. put（）5. —Let’s clean the desks and chairs.—________A. OK.B. Hello.C. Thank you.四、Read and circle.（读一读，圈出正确的单词。

）1. Look! This ________ （is, are）my new classroom.2. The floor is green. The ________ （teacher, teacher’s）desk is yellow.3. Let ________ （I, me）clean the blackboard.4. Three ________ （desk, desks）are yellow.5.We ________ （have, has）a new teacher.五、Read and choose.（读一读，选择合适的单词完成句子。

四年级英语上册 Unit1 My classroom 单元测试人教版（PEP）（含答案及解析）一、单选题（共10题）1.—Who is that_____? —She's my sister.A.boyB.girlC.man2.—Excuse me，Jack. Where is the bus?—___________.A.In the treeB.On the treeC.Near the tree3.—Let's clean the classroom.—_________A.OK!B.Goodbye!C.Thank you.4.—Where's my ruler?—________A.It's so big.B.It's in the desk.C.It's a bag.5.—Let me help you.—________A.Really?B.Thank you.C.All right.6.—Sarah, we have a new classroom.—________ Let's go and have a look.A.Really?B.Thank you.C.All right.7.—Where is my picture?—________A.It's near the window.B.It's a bee.C.It's so big.8.________ the blackboard, please.A.SweepB.CleanC.Open9.—________is my ruler?—It's on the desk.A.WhatB.What colourC.Where10.— _________ is your pencil?—It's on the desk.A.WhatB.WhereC.How二、填空题（共2题）11.判断下面每组单词画线部分读音是否相同。

Unit 1 My classroom 测试卷听力部分(40分)一、听录音，选出你所听到的单词。

(10分)( )1. A. classroom B. blackboard C.schoolbag ( )2. A. window B. light C. door( )3. A. open B.crayon C. clean( )4. A. cat B. hat C. dad( )5. A. near B. picture C. chair二、听录音，判断下列句子与你所听内容是(T)否(F)一致。

(10分( )1. It's near the window.( )2. It's a light.( )3. Close the door.( )4. Where is the classroom?( )5. I have a new crayon.三、听录音，给下面的图片排序。

(10分)( ) ( ) ( )( ) ( )四、听录音，选择恰当的应答语。

(10分)( )1. A. It's blue. B. It's on the wall.( )2. A It's a fan B. One blackboard, many desks and chairs. ( )3. A. OK. B. Excuse me.( )4. A. You're welcome. B. Thank you.( )5. A. The door is orange. B It's a bee.笔试部分(60分)五、选出每组单词中字母a读音不同的一项。

(5分)( )1. A. cat B. cake C. hat( )2.A.thank B.date C.bag( )3. A. face B. dad C name( )4. A. hate B. make C. blackboard( )5. A. fan B. classroom C. black六、单项选择我最棒。

单元测试卷一、选择题1.A.dad B.hate C.hat2.A.face B.cap C.map3.A.cat B.cake C.make4.A.bag B.fat C.date B.grape C.black6.We ________ six new lights.( )A. areB. hasC. have7.She ________ a new pen.( )A. isB. hasC. have8.Let’s ________ the classroom.( )A. cleanB. to cleanC. cleaning9.Let ________ clean the teacher’s desk.( )A. meB. IC. my10.—________ in the classroom?( )—Some desks and chairs.A. WhatB. What’sC. Where’s11.—________( )—It’s on the floor.A. What’s in it?B. Who is it?C. Where is it?12.( )—Where is my dog?—It’s ________ the desk.A. inB. onC. under 评卷人得分二、匹配题light door window picture computer13.________14.________15.________16.________17.________读句子，选择正确的汉语意思A.它在讲台附近。

B.教室里有什么？C.它在哪儿？D.我来擦黑板。

E.我们去看看吧！18.Where is it?（_______）19.It’s near the teacher’s desk.（_______）20.What’s in the classroom?（_______）21.Let’s go and see!（_______）22.Let me clean the blackboard.（_______）评卷人得分三、看图题23.cl __ ssr ____ m24.t ____cher’s d __ sk25.f __ n26.bl __ ckb ______d27.fl ____ r28.w __ ll评卷人得分四、看图仿写看图，仿照例子写对话例：(cat, desk)—Where is the cat?—It’s under the desk.29.(fan, wall)________________30.(computer, desk)________________31.(chair, desk)________________评卷人得分五、补全对话A.What’s in the classroom?B.Let me help you.C.Where is the fan?D.Let’s clean the classroom.32.A:________B:Thank you33.A:________B:A blackboard,some desks and chairs…34.A:________B:OK35.A: ________B:It’s on the desk.评卷人得分六、情景交际:_______( )A. Let me clean the desks.B. Let’s clean the desks.37.当你对朋友说你来擦课桌时，你应该说:________( )A. Let me clean the desks.B. Let’s clean the desks.38.Zoom想知道Zip的铅笔盒里有什么，应该问Zip:________( )A. What’s in your pencil box?B. Where’s your pencil box?。

四年级英语上Unit1 my classroom单元测试题总分：100分时间：40分钟得分__________一、根据中文提示，在横线上填上适当的字母。

(8分)1．f____n(风扇)2．w____ ____l (墙)3．fl____ ____r (地板) 4．c____mp____t____r(电脑)二、圈出与其他不同类的单词。

(4分)1. duck bus car2．teacher desk chair3．floor light boy4．TV classroom fan三、选择相应的图片。

（10分）()1.window A. B. C.()2.picture A. B. C.()3.bed A. B. C.()4.desk A. B. C.()5.light A. B. C.四、给单词或短语选择正确的汉语意思。

(20分)()1.many()2.our()3.classmate ()4.have a look()5.seat ()6.near()7.clean ()8.good idea()9.all right ()10.good job A．干得好B．好主意C．座位D．许多的E．同学F．好吧；好的G．看一看H．我们的I．打扫；清洁；擦干净的J．在……的旁边五、选出不同类的一项。

(10分)()1.A.hat B．board C．desk ()2.A.bread B．good C．cake ()3.A.light B．fan C．school ()4.A.boy B．idea C．girl()5.A.cat B．ant C．egg()6.A.box B．six C seven ()7.A.peach B．lamp C．apple ()8.A.teacher B．doctor C．desk ()9.A.bread B．cake C．hand ()10.A.chair B．desk C．dog 六、单项选择。

四年级英语上Unit1 my classroom单元测试题总分：100分时间：40分钟得分__________一、根据中文提示，在横线上填上适当的字母。

(8分)1．f____n(风扇) 2．w____ ____l (墙)3．fl____ ____r (地板) 4．c____mp____t____r(电脑)二、圈出与其他不同类的单词。

(4分)1. duck bus car2．teacher desk chair3．floor light boy4．TV classroom fan三、选择相应的图片。

（10分）( )1.window A. B. C.( )2.picture A. B. C.( )3.bed A. B. C.( )4.desk A. B. C.( )5.light A. B. C. 四、给单词或短语选择正确的汉语意思。

(20分)( )1.many ( )2.our( )3.classmate ( )4.have a look( )5.seat ( )6.near( )7.clean ( )8.good idea( )9.all right ( )10.good jobA．干得好B．好主意C．座位D．许多的 E．同学F．好吧；好的G．看一看H．我们的I．打扫；清洁；擦干净的 J．在……的旁边五、选出不同类的一项。

(10分)( )1.A.hat B．board C．desk( )2.A.bread B．good C．cake( )3.A.light B．fan C．school( )4.A.boy B．idea C．girl( )5.A.cat B．ant C．egg( )6.A.box B．six C seven( )7.A.peach B．lamp C．apple( )8.A.teacher B．doctor C．desk( )9.A.bread B．cake C．hand( )10.A.chair B．desk C．dog六、单项选择。

四年级英语上Unit1 my classroom单元测试题总分：100分时间：40分钟得分__________一、根据中文提示，在横线上填上适当的字母。

(8分)1．f____n(风扇)2．w____ ____l (墙)3．fl____ ____r (地板) 4．c____mp____t____r(电脑)二、圈出与其他不同类的单词。

(4分)1. duck bus car2．teacher desk chair3．floor light boy4．TV classroom fan三、选择相应的图片。

（10分）()1.window A. B. C.()2.picture A. B. C.()3.bed A. B. C.()4.desk A. B. C.()5.light A. B. C.四、给单词或短语选择正确的汉语意思。

(20分)()1.many()2.our()3.classmate ()4.have a look()5.seat ()6.near()7.clean ()8.good idea()9.all right ()10.good jobA．干得好B．好主意C．座位D．许多的E．同学F．好吧；好的G．看一看H．我们的I．打扫；清洁；擦干净的J．在……的旁边五、选出不同类的一项。

(10分)()1.A.hat B．board C．desk()2.A.bread B．good C．cake()3.A.light B．fan C．school ()4.A.boy B．idea C．girl()5.A.cat B．ant C．egg()6.A.box B．six C seven()7.A.peach B．lamp C．apple()8.A.teacher B．doctor C．desk()9.A.bread B．cake C．hand()10.A.chair B．desk C．dog六、单项选择。

(6分)()1.We have six new________.A．light B．lights C．the light ()2.My classroom is so________！A．tall B．big C．best ()3.We________ new classroom.A．has B．have C．have a ()4.Let's go________have a look.A．and B．/ C．to()5.I have a________idea.A．well B．good C．great()6.The sharpener is near the fish________.A．bowl B．glass C．cup 七、情景交际。

四年级英语上Unit1 my classroom单元测试题总分：100分时间：40分钟得分__________一、根据中文提示，在横线上填上适当的字母。

(8分)1．f____n(风扇)2．w____ ____l (墙)3．fl____ ____r (地板) 4．c____mp____t____r(电脑)二、圈出与其他不同类的单词。

(4分)1. duck bus car2．teacher desk chair3．floor light boy4．TV classroom fan三、选择相应的图片。

（10分）()1.window A. B. C.()2.picture A. B. C.()3.bed A. B. C.()4.desk A. B. C.()5.light A. B. C. 四、给单词或短语选择正确的汉语意思。

(20分)()1.many()2.our()3.classmate ()4.have a look()5.seat ()6.near()7.clean ()8.good idea()9.all right ()10.good job A．干得好B．好主意C．座位D．许多的E．同学F．好吧；好的G．看一看H．我们的I．打扫；清洁；擦干净的J．在……的旁边五、选出不同类的一项。

(10分)()1.A.hat B．board C．desk ()2.A.bread B．good C．cake ()3.A.light B．fan C．school ()4.A.boy B．idea C．girl()5.A.cat B．ant C．egg()6.A.box B．six C seven ()7.A.peach B．lamp C．apple ()8.A.teacher B．doctor C．desk ()9.A.bread B．cake C．hand()10.A.chair B．desk C．dog 六、单项选择。