名校试题精校解析 Word版---黑龙江省鹤岗市第一中学高三上学期第三次月考数学(理)
- 格式:docx
- 大小:416.62 KB
- 文档页数:9
鹤岗市第一中学2019届高三上学期第三次月考英语试题一.单项选择(共20小题;每小题1分,满分20分)从每题所给的A、B、C和D四个选项中,选出最佳选项。
1. Before you start, it seems that the task is _____________ to be accomplished.A. possibleB. unlikelyC. impossibleD. probable2. You are supposed to _____________ the work, but I haven’t seen it now.A. have been finishedB. be finishingC. have finishedD. finish3. Unfortunately, fifteen-year-old Paige suffers from _______________ rare brain disease, which affects as few as 12 people in the world, and could kill her any day _______________ warning.A. a; withoutB. the; withoutC. a; withD. the; with4. With such a tight schedule, everyone will have to go all out if they_____________ the task.A. have completedB. would completeC. will completeD. are to complete5. I _____________ to look upon life as a process of getting.A. was brought upB. was brought inC. was brought outD. was brought forward6. This happens _____________ the children are in two-parent or one-parent families.A. no matterB. eitherC. ifD. whether7. The orphan enjoyed a pleasant evening in the _____________ of the volunteers.A. accompanyB. companionC. companyD. companionship8. He is a professor, _____________ I have been looking forward to becoming.A. whichB. whoC. whomD. that9. He was giving his collection _____________ for free.A. upB. awayC. offD. back10. Greta has always tended to keep her colleagues _____________.A. in a distanceB. in the distanceC. at a distanceD. at the distance11. _____________ you are trying to lose weight to please yourself, it’s going to be tough to keep your motivation level high.A. IfB. WhenC. BecauseD. Unless12. Why not _____________ what you enjoy and do that?A. discoverB. to discover D. discovering D. discovered13. It is a great evening, and definitely _____________ all the hard work.A. worthyB. worthC. worthwhileD. worthless14. The producer comes regularly to collect the cameras _______________ to our shop for quality problems.A. returningB. being returnedC. returnedD. to be returned15. _______________ they got the machine tool repaired.A. At no timeB. In no timeC. At one timeD. In one time16. The way the guests ________ in the hotel influenced their evaluation of the service.A. treatedB. were treatedC. would treatD. would be treated17. The hotel is currently _______________ construction.A. inB. ofC. onD. under18. You can’t _______________ on anybody to keep your secret.A. relyB. trustC. believeD. support19. Some people waste too much water. They don’t believe that it can_____________ some day.A. use upB. run out ofC. be run outD. run out20. That’s the way I look at most of _______________ has happened to me.A. thatB. whichC. whatD. all二.阅读理解(共15小题;每小题2分,满分30分)阅读下列短文,从每题所给的A、B、C和D四个选项中,选出最佳选项,并在答题卡上将该项涂黑。
鹤岗一中高三第三次月考理科数学一、选择题共12小题,每小题5分,共60分.在每小题列出的四个选项中,选出符合题目要求的一项1.设集合{}21log 3A x x =≤≤,{}2340B x x x =--<,则A B =( )A. ()1,2-B. (]1,8-C. [)2,4D. []4,8【答案】B 【解析】 【分析】求出集合A ,集合B ,然后求交集即可.【详解】解:因为{}28A x x =≤≤,{}14B x x =-<<,所以{}18A B x x ⋃=-<≤. 故选B.【点睛】本题考查集合交集的运算,以及对数不等式,二次不等式的求解,是基础题.2.在复平面内,复数21ii+-对应的点位于( ) A. 第一象限 B. 第二象限C. 第三象限D. 第四象限【答案】A 【解析】 【分析】直接利用复数代数形式的乘除运算化简得答案.【详解】解:()()()()21+21+3i==111+2i i i i i i ++--, 所以复数21i i +-对应的点的坐标为:13,22⎛⎫⎪⎝⎭,位于第一象限, 故选A .【点睛】本题考查复数代数形式的乘除运算,考查复数的代数表示法及其几何意义,是基础题.3.设l 为直线,,αβ是两个不同的平面,下列命题中正确的是( )A. 若//l α,//l β,则//αβB. 若l α⊥,l β⊥,则//αβC. 若l α⊥,//l β,则//αβD. 若αβ⊥,//l α,则l β⊥【答案】B 【解析】A 中,,αβ也可能相交;B 中,垂直与同一条直线的两个平面平行,故正确;C 中,,αβ也可能相交;D 中,l 也可能在平面β内. 【考点定位】点线面的位置关系4.已知一组样本数据点11223366(,),(,),(,),,(,)x y x y x y x y ,用最小二乘法求得其线性回归方程为24y x =-+.若1236,,,,x x x x 的平均数为1,则1236y y y y ++++=( )A. 10B. 12C. 13D. 14【答案】B 【解析】 【分析】设样本数据的中心为(1,)y ,代入回归直线的方程,求得2y =,进而求得答案.【详解】由题意,设样本数据的中心为(1,)y ,代入回归直线的方程,可得2142y =-⨯+=,则1234566212y y y y y y +++++=⨯=,故选B .【点睛】本题主要考查了回归直线方程的应用,其中解答中熟记回归直线方程的基本特征是解答本题的关键,着重考查了推理与运算能力,属于基础题. 5.已知等比数列{}n a 满足112a =,且()24341a a a ⋅=-,则5a =( ) A. 8 B. 16C. 32D. 64【答案】A 【解析】 【分析】先由题意求出公比,再根据等比数列的通项公式即可求出5a 的值【详解】等比数列{}n a 满足112a =,且2434(1)a a a =-, 则321114(1)222q q q ⨯⨯⨯=⨯-, 解得24q =,42511482a a q ∴==⨯=,故选A .【点睛】本题考查了等比数列的通项公式,考查了运算求解能力,属于基础题. 6.点()1,2P -是角α终边上一点,则()sin πα-的值为( )B. C. 25-D.15【答案】A 【解析】 【分析】利用三角函数的定义求出sin α的值,然后利用诱导公式可求出()sin πα-的值.【详解】由三角函数的定义可得sin α==,由诱导公式可得()sin sin παα-==故选A.【点睛】本题考查三角函数的定义,同时也考查了利用诱导公式求值,在利用诱导公式求值时,充分理解“奇变偶不变,符号看象限”这个规律,考查计算能力,属于基础题. 7.下列叙述正确的是( )A. 命题“p 且q ”为真,则,p q 恰有一个为真命题B. 命题“已知,a b ∈R ,则“a b >”是“22a b >”的充分不必要条件”C. 命题:0p x ∀>都有e 1x >,则0:0p x ⌝∃>,使得01x e ≤D. 如果函数()y f x =在区间(,)a b 上是连续不断的一条曲线,并且有()0)·(f a f b <,那么函数()y f x =在区间(,)a b 内有零点【答案】C 【解析】 【分析】由p 且q 的真值表,可判断正误;由充分必要条件的定义和特值法,可判断正误;由全称命题的否定为特称命题,可判断正误;由函数零点存在定理可判断正误. 【详解】解:对于A ,命题“P 且q 为真,则P ,q 均为真命题”,故错误;对于B ,“a >b ”推不出“a 2>b 2”,比如a =1,b =﹣1;反之也推不出,比如a =﹣2,b =0,“a >b ”是“a 2>b 2”的不充分不必要条件,故错误;对于C ,命题:0p x ∀>都有e 1x >,则0:0p x ⌝∃>,使得01x e ≤,故正确; 对于D ,如果函数y =f (x )在区间[a ,b ]上是连续不断的一条曲线,并且有f (a )•f (b )<0,由零点存在定理可得函数y =f (x )在区间(a ,b )内有零点,故错误.其中真命题的个数为1, 故选C .【点睛】本题考查命题的真假判断,考查命题的否定和充分必要条件的判断,以及函数零点存在定理和函数的单调性的判断,考查判断能力和运算能力,属于中档题. 8.函数()sin()(0)4f x A x πωω=+>的图象与x 轴交点的横坐标构成一个公差为3π的等差数列,要得到函数()cos g x A x ω=的图象,只需将()f x 的图象( )A. 向左平移12π个单位 B. 向右平移4π个单位 C. 向左平移4π个单位 D. 向右平移34π个单位 【答案】A 【解析】依题意有()f x 的周期为()22ππ,3,sin 334T f x A x πωω⎛⎫====+ ⎪⎝⎭.而()πππππsin 3sin 3sin 3244124g x A x A x A x ⎡⎤⎛⎫⎛⎫⎛⎫=+=++=++ ⎪ ⎪ ⎪⎢⎥⎝⎭⎝⎭⎝⎭⎣⎦,故应左移π12.9.己知椭圆()222210x y a b a b+=>>直线l 过左焦点且倾斜角为3π,以椭圆的长轴为直径的圆截l 所得的弦长等于椭圆的焦距,则椭圆的离心率为( )A.7【答案】D 【解析】 【分析】假设直线方程,求得圆心到直线的距离d,利用弦长等于,a c 的齐次方程,从而求得离心率.【详解】由题意知,椭圆左焦点为(),0c -,长轴长为2a ,焦距为2c 设直线l方程为:)y x c =+0y -+= 则以椭圆长轴为直径的圆的圆心为()0,0,半径为a∴圆心到直线l的距离2d ==2c ∴==,整理得:2247c a =∴椭圆的离心率为c a ==本题正确选项:D【点睛】本题考查椭圆离心率的求解,关键是能够利用直线被圆截得的弦长构造出关于,a c 的齐次方程.10.在三棱锥P ABC -中,点P A B C ,,,均在球O 的球面上,且86AB BC AB BC ⊥==,,,若此三棱锥体积的最大值为O 的表面积为( )A. 90πB. 120πC. 160πD. 180π【答案】D 【解析】 【分析】根据条件可知,当球心在三棱锥P ABC -的高上时,此三棱锥的体积最大.根据数形结合,设半径为R ,1OO A ∆是直角三角形,满足22211AO AO OO =+,建立关于R的方程,最后24S R π=计算表面积.【详解】因为三棱锥P ABC -的底面积一定,所以当球心在三棱锥P ABC -的高上时, 此三棱锥的体积最大.设球O 的半径为R ,顶点P 在底面内的射影为1O .因为AB BC ⊥,所以1O 为斜边AC 的中点,则152AC AO ===,如图所示.由三楼锥P ABC -的体积113ABC V S PO ∆=⋅得1118632PO =⨯⨯⨯⨯ ,解得1PO =在1Rt AOO ∆中,有22211AO AO OO =+,即2225)R R =+,解得R =,故球O 的表面积2244180S R πππ===球 .【点睛】本题考查了球与几何体综合问题,考查空间想象能力以及化归和计算能力,(1)当三棱锥的三条侧棱两两垂直时,并且侧棱长为,,a b c,那么外接球的直径2R =(2)当有一条侧棱垂直于底面时,先找底面外接圆的圆心,过圆心做底面的垂线,球心在垂线上,根据垂直关系建立R 的方程.11.已知()f x 是定义在R 上的偶函数,满足()()2f x f x +=,当[]0,1x ∈时,()3f x x x =+,若24log 5a f ⎛⎫= ⎪⎝⎭,()2log 4.1b f =,()2019c f =,则a ,b ,c 的大小关系为( ) A. a b c <<B. b a c <<C. c a b <<D.c a b <<【答案】B 【解析】 【分析】根据题意,分析可得函数f (x )是周期为2的周期函数,据此可得c =f (2019)=f (1+2×1007)=f (1),b =f (log 24.1)=f (log 24.1﹣2)=f (log 24.14),结合函数的奇偶性可得a =f (log 245)=f (﹣log 245)=f (log 254),结合函数解析式可得f (x )在[0,1]上为增函数,据此分析可得答案.【详解】根据题意,f (x )满足f (x +2)=f (x ),即函数f (x )是周期为2的周期函数, 则c =f (2019)=f (1+2×1009)=f (1),b =f (log 24.1)=f (log 24.1﹣2)=f (log 24.14),的又由f (x )为偶函数,则a =f (log 245)=f (﹣log 245)=f (log 254), 当x ∈[0,1]时,f (x )=x 3+x ,易得f (x )在[0,1]上为增函数,又由0<log 24.14<log 254<1,则有b <a <c ; 故选B .【点睛】本题考查函数的奇偶性与周期性的综合应用,注意分析函数的周期,属于基础题.12.已知椭圆22:182x y C +=的左、右焦点分别为12,F F ,直线l 过点2F 且与椭圆C 交于M N ,两点,且MA AN =,若2||OA AF =,则直线l 的斜率为( )A. ±1B. 12±C. 13±D. 14±【答案】B 【解析】 【分析】设()()1122,,,M x y N x y ,利用点差法可得: 14OA MN k k ⋅=-,再根据△2OAF 为等腰三角形,可得OA MN k k =-,联立两个方程可解得12MN k =±,即得直线l 斜率.【详解】如图:设()()1122,,,M x y N x y ,则22112222182182x y x y ⎧+=⎪⎪⎨⎪+=⎪⎩,两式相减可得()()()()12121212082x x x x y y y y -+-++=,则14OA MNkk ⋅=-;因为2||OA AF =,所以△2OAF 为等腰三角形,故OA MN k k =- ,解得12MN k =±,故直线l 的斜率为12±【点睛】本题考查了椭圆的标准方程以及直线的斜率,属中档题. 二、填空题共4小题,每题5分,满分20分,将答案填在答题纸上) 13.“实数1m =-”是“向量(,1)a m =与向量(2,3)bm 平行”____________的条件(从“充分不必要”“必要不充分”“充分必要”“既不充分也不必要”中选择恰当的一个填空) .【答案】充分必要 【解析】 【分析】由向量共线的判断及向量共线的坐标运算可得解.【详解】解:当1m =-时,(1,1),(3,3)a b =-=- ,即3b a =,所以a b ;当a b 时,31(2)0m m ⨯-⨯-=,解得1m =-,故“1m =-”是“a b ”的充分必要条件.【点睛】本题考查了共线向量及充分必要条件,属基础题.14.设a ,b 为正实数,且214b a a b a b ⎛⎫+=+ ⎪⎝⎭,则221b a b a ++的最小值为____. 【答案】4【解析】【分析】 由214()b a a b a b +=+,展开可解得22124a b a a b b a b ++=+,进而可得22122b a b a b a b a ++=+,利用基本不等式解出即可. 【详解】因为214()b a a b a b +=+,所以22124a b a a b b a b++=+;所以221224b a b a b a b a ++=+≥=,当且仅当a =b 成立 故答案为4.【点睛】本题主要考查基本不等式的应用,配凑定值是关键,属于中档题.15.设函数ln ,0()(1),0x x x f x x e x ⎧>=⎨+≤⎩,若函数()()g x f x b =-有三个零点,则实数b 的取值范围是____.【答案】(0,1]【解析】将问题转化为()y f x =与y b =有三个不同的交点;在同一坐标系中画出()y f x =与y b =的图象,根据图象有三个交点可确定所求取值范围.【详解】函数()()g x f x b =-有三个零点等价于()y f x =与y b =有三个不同的交点 当0x ≤时,()()1x f x x e =+,则()()()12x x xf x e x e x e '=++=+ ()f x ∴在(),2-∞-上单调递减,在(]2,0-上单调递增且()212f e-=-,()01f =,()lim 0x f x →-∞= 从而可得()f x 图象如下图所示:通过图象可知,若()y f x =与y b =有三个不同的交点,则(]0,1b ∈本题正确结果:(]0,1【点睛】本题考察根据函数零点个数求解参数取值范围的问题,关键是将问题转化为曲线和直线的交点个数问题,通过数形结合的方式求得结果.16.在ABC ∆中,角,,A B C 所对的边分别为,,,60a b c ABC ABC ︒∠=∠的平分线交AC 于点D ,且1BD =,则4a c +的最小值为_________【答案】【分析】根据面积关系建立方程关系,结合基本不等式1的代换进行求解即可. 【详解】解:由题意得12ac sin60°12=a sin30°12+c sin30°,=a +c ,得11a c+=, 得4a +c(4a +c )(11a c +)45c a a c ⎫=++⎪⎝⎭5⎫⎪⎪⎝⎭=, 当且仅当4c a a c=,即c =2a 时,取等号,故答案为.【点睛】本题主要考查基本不等式的应用与三角形的面积公式,利用1的代换结合基本不等式是解决本题的关键.三、解答题 (本大题共6小题,共70分.解答应写出文字说明、证明过程或演算步骤.)17.已知数列{}n a 中,12a =,1122n n n a a ++=+,设2n n na b =. (Ⅰ)求证:数列{}n b 是等差数列; (Ⅱ)求数列11{}n n b b +的前n 项和n S . 【答案】(Ⅰ)见证明;(Ⅱ)111n S n =-+ 【解析】【分析】(1)证明1n n b b c --=(c 为常数)即可;(2)将11n n b b +采用裂项的方式先拆开,然后利用裂项相消的求和方法求解n S . 【详解】(Ⅰ)证明:当2n ≥时,111121222n n n n n n n n na a a ab b ------=-== 11b =,所以{}n b 是以为1首项,为1公差的等差数列.(Ⅱ)由(Ⅰ)可知,n b n =,所以+11111n n b b n n =-+, 所以1111111122311n S n n n =-+-++-=-++. 【点睛】常见的裂项相消形式:(1)111(1)1nn n n =-++;(2= (3)1111()(21)(21)22121n n n n =--+-+; (4)112311(31)(31)3131n n n nn ++=-----. 18.某花圃为提高某品种花苗质量,开展技术创新活动,在A ,B 实验地分别用甲、乙方法培训该品种花苗.为观测其生长情况,分别在实验地随机抽取各50株,对每株进行综合评分,将每株所得的综合评分制成如图所示的频率分布直方图.记综合评分为80及以上的花苗为优质花苗.(1)求图中a的值;(2)填写下面的列联表,并判断是否有90%的把握认为优质花苗与培育方法有关.附:下面的临界值表仅供参考.(参考公式:22()()()()()n ad bcKa b c d a c b d-=++++,其中n a b c d=+++.)【答案】(1)0.040;(2)列联表见解析,有90%把握认为优质花苗与培育方法有关系. 【解析】【分析】(1)根据频率分布直方图中矩形面积之和为1即可求解;(2)根据题中“分别在实验地随机抽取各50株”判断即可补全数据,再根据二联表算出2K,并结合2K与0K的关系判断即可【详解】(1)0.005100.01000.02510100.020101a ⨯+⨯+⨯+⨯+⨯=,解得0.040a = ;(2) 结合(1)与频率分布直方图,优质花苗的频率为(0.040.02)100.6+⨯=,则样本种,优质花苗的颗数为60棵,列联表如下表所示:可得22100(20103040)16.667 2.70660405050K ⨯-⨯=≈>⨯⨯⨯. 所以,有90%的把握认为优质花苗与培育方法有关系.【点睛】本题考查频率分布直方图中具体值的计算,解题关键在于抓住图形中面积之和为1进行求解,二联表的填写,2K 的计算和相关性的判断,属于中档题19.如图,在直角梯形ABED 中,//, AB ED AB EB ⊥,点C 是AB 中点,且,24AB CD AB CD ⊥==,现将三角形ACD 沿CD 折起,使点A 到达点P 的位置,且PE 与平面PBC 所成的角为45.(1)求证:平面PBC ⊥平面DEBC ;(2)求二面角D PE B--余弦值.【答案】(1)见解析; (2)7-. 【解析】【分析】(1)可证CD ⊥平面PBC ,从而可证平面PBC ⊥平面DEBC .(2)以O 为坐标原点,过点O 与BE 平行的直线为x 轴,CB 所在的直线y 轴OP 所在的直线为z 轴建立空间直角坐标系, 求出平面PDE 和平面PEB 的法向量后可求二面角的余弦值.【详解】(1)证明:在平面ABED 中,, AB CD BC CD ⊥⊥ PC 为AC 沿CD 折起得到,PC CD ∴⊥PCBC C CD =⊥,平面PBC , 又CD ⊂平面,DEBC ∴平面PBC ⊥平面DEBC(2)解:在平面ABED 中, //AB CD AB BE CD EB ⊥⊥,,由(1)知CD ⊥平面PBC EB ∴⊥,平面PBC ,而PB ⊂平面PBC ,故EB PB ⊥. 由PE 与平面PBC 所成的角为45,得45EPB ∠=,PBE ∴∆为等腰直角三角形,PB EB ∴=,//AB DE ,又//CD EB ,得2BE CD ==,2PB ∴=,故PBC ∆为等边三角形,的取BC 的中点O ,连结PO ,,PO BC PO ⊥∴⊥平面EBCD ,以O 为坐标原点,过点O 与BE 平行的直线为x 轴,CB 所在的直线y 轴OP 所在的直 线为z 轴建立空间直角坐标系如图,则()()0,1,02,1,0B E ,,()2,1,0()D P -, 从而()()0,2,02,0,01(2,,DE BE PE ===,,, 设平面PDE 的一个法向量为(), , m x y z =, 平面PEB 的一个法向量为(), , n a b c =,则由00m DE m PE ⎧⋅=⎨⋅=⎩得20230y x y z =⎧⎪⎨+-=⎪⎩,令2z =-得()3,0,2m =--, 由00n BE n PE ⎧⋅=⎨⋅=⎩得2020a a b =⎧⎪⎨+=⎪⎩,令1c =得()0,3,1n =,所以cos 7m nm n m n ⋅===⨯⋅,, 设二面角D PE B --的大小为θ,则θ为钝角且7cos θ=-, 即二面角D PE B --的余弦值为【点睛】面面垂直的证明可以通过线面垂直得到,也可以通过证明二面角是直二面角. 空间中的角的计算,可以建立空间直角坐标系把角的计算归结为向量的夹角的计算,也可以构建空间角,把角的计算归结平面图形中的角的计算.20.如图,椭圆1C :22221(0)x y a b a b +=>>的左右焦点分别为12,F F,过抛物线2C :24x by =焦点F 的直线交抛物线于,M N 两点,当7||4MF =时,M 点在x 轴上的射影为1F ,连接,)NO MO 并延长分别交1C 于,A B 两点,连接AB ,OMN ∆与OAB ∆的面积分别记为OMN S ∆,OAB S ∆,设λ=OMN OABS S ∆∆.(1)求椭圆1C 和抛物线2C 的方程;(2)求λ的取值范围.【答案】(I ) 2214x y +=,24x y =;(II ) [)2,+∞. 【解析】试题分析:(Ⅰ )由题意得得7,4M c b ⎛⎫-- ⎪⎝⎭,根据点M 在抛物线上得2744c b b ⎛⎫=- ⎪⎝⎭,又由2c a =,得 223c b =,可得277b b =,解得1b =,从而得2c a ==,可得曲线方程.(Ⅱ )设ON k m =,'OM k m =,分析可得1'4m m=-,先设出直线ON 的方程为y mx = (0)m >,由24y mx x y=⎧⎨=⎩,解得4N x m =,从而可求得4ON =,同理可得,,OM OA OB ,故可将=OMN OAB ON OM S S OA OBλ∆∆⋅=⋅化为m 的代数式,用基本不等式求解可得结果.试题解析: (Ⅰ)由抛物线定义可得7,4M c b ⎛⎫-- ⎪⎝⎭, ∵点M 在抛物线24x by =上, ∴2744c b b ⎛⎫=- ⎪⎝⎭,即2274c b b =- ①又由c a = 223c b = 将上式代入①,得277b b =解得1,b =∴c =2a ∴=,所以曲线1C 的方程为2214x y +=,曲线2C 的方程为24x y =.(Ⅱ)设直线MN 的方程为1y kx =+,由214y kx x y=+⎧⎨=⎩消去y 整理得2440x kx --=, 设11,)Mx y (,()2,2N x y . 则124x x =-,设ON k m =,'OM k m =,则21122111'164y y mm x x x x =⋅==-, 所以1'4m m=-, ② 设直线ON 的方程为y mx = (0)m >,由24y mx x y =⎧⎨=⎩,解得4N x m =,所以4N ON ==, 由②可知,用14m-代替m ,可得M OM == 由2214y mxx y =⎧⎪⎨+=⎪⎩,解得A x =,所以A OA ==用14m-代替m,可得BOB==所以=OMNOABON OMSS OA OBλ∆∆⋅==⋅==1222mm=+≥,当且仅当1m=时等号成立.所以λ取值范围为[)2,+∞.点睛:解决圆锥曲线的最值与范围问题时,若题目的条件和结论能体现一种明确的函数关系,则可首先建立目标函数,再求这个函数的最值.常从以下几个方面考虑:①利用判别式来构造不等关系,从而确定参数的取值范围;②利用隐含或已知的不等关系建立不等式,从而求出参数的取值范围;③利用基本不等式求出参数的取值范围;④利用函数的值域的求法,确定参数的取值范围.21.已知函数()()()221lnf x a x ax a Rx=---∈.(Ⅰ)当1a=时,求()f x的单调区间;(Ⅱ)设函数()()12xe ax ag x f xx--+=+,若2x=是()g x的唯一极值点,求a.的【答案】(1)()f x 在(0,2)上单调递增;在(2,)+∞上单调递减;(2)0a = 【解析】 【分析】(1)当1a =时, ()2ln f x x x x=--,定义域为()0,∞+,求导,解()0f x '>,即可得出单调性.(2)由题意可得:()()12221ln x e ax ag x a x ax x x--+=----,求导得()()()x 123x 2e ax x a g'x x ----+=,由于2x =是()g x 的唯一极值点,则有以下两种情形:情形一:120x e ax x a ---+≥对()0,x ∀∈+∞恒成立.情形二:120x e ax x a ---+≤对()0,x ∀∈+∞恒成立.设,对a 分类讨论,利用导数研究函数的单调性极值与最值即可得出.【详解】解:(1)当1a =时, ()2ln f x x x x=--,定义域为()0,∞+. ()()()22x 1x 212'1xf x x x -+-=-+=, 解()0f x '>,解得02x <<.∴函数()f x 在()0,2上单调递增;在()2,+∞上单调递减.(2)由题意可得:()()12221ln x e ax ag x a x ax x x--+=----,()0,x ∈+∞. ()()()x 12x 124ea x e ax a 2x212g'x a xa xx-----+⋅-=-++()()1232x x e ax x a x ----+=,()0,x ∈+∞.由于2x =是()g x 的唯一极值点,则有以下两种情形: 情形一:120x e ax x a ---+≥对()0,x ∀∈+∞恒成立. 情形二:120x e ax x a ---+≤对()0,x ∀∈+∞恒成立.设.()1'21x h x eax -=--.①当0a =时,()1'1x h x e-=-.则()'10h =.可得1x =时,函数()h x 取得极小值即最小值,∴()()10h x h ≥=.满足题意.②当0a <时,.在()0,x ∈+∞单调递增.又.∴存在()00,1x ∈,使得()0'0h x =.当0x x >时,()'0h x >,()h x 在()0,x +∞单调递增,∴()()()0102h x h h <=<,这与题意不符. ③当0a >时,设.()1'2x p x ea -=-,令()'0p x =,解得()1ln 2x a =+.可得()p x 在()(),1ln 2a -∞+上单调递减;在()()1ln 2,a ++∞上单调递增.i )当12a >时,()1ln 21a +>,由()'h x 在()()0,1ln 2a +上单调递减, 可得()()''00h x h <<,()h x 在()()0,1ln 2a +上单调递减,∴()()()1101ln 22h h h a ⎛⎫>=>+ ⎪⎝⎭,这与题意矛盾,舍去.ii )当102a <≤时,()1ln 21a +≤ ,由()()'h x p x =的单调性及()'00h <, 可知:()0,1x ∈时,都有()'0h x <.又()'h x 在()1,3上单调递增,()221'3616102h e a e =--≥-⨯->, 则存在()11,3x ∈,使得()10h x =.∴()10,x x ∈时,()'0h x <,此时()h x 单调递减,∴()()11h 102h h x ⎛⎫>=>⎪⎝⎭,这与题意矛盾,舍去. 综上可得:0a =.【点睛】本题考查了利用导数研究函数的单调性极值与最值、方程与不等式的解法、等价转化方法、分类讨论方法,考查了推理能力与计算能力,属于难题.请考生在22、23两题中任选一题作答,如果多做,则按所做的的第一题记分. 选修4-4:坐标系与参数方程22.在平面直角坐标系xOy 中,曲线C 的参数方程为12cos 12sin x y θθ=-+⎧⎨=+⎩(θ为参数).(Ⅰ)求曲线C 的普通方程;(Ⅱ)经过点2()1,M -作直线l 交曲线C 于A ,B 两点,若M 恰好为线段AB 的三等分点,求直线l 的普通方程.【答案】(1)()()22114x y ++-=(25100y -+=5100y +=. 【解析】 【分析】(1)根据三角函数的基本关系式,消去参数,即可得到曲线C 的普通方程; (2)联立直线l 的参数方程和曲线C 的普通方程,根据参数的几何意义,即可求解.【详解】(1)由曲线C 的参数方程,得1212x cos y sin θθ+=⎧⎨-=⎩(θ为参数),所以曲线C 的普通方程为()()22x 1y 14++-=.(2)设直线l 的倾斜角为α,则直线的参数方程为12x cos y tsin αα=-+⎧⎨=+⎩(t 为参数),代入曲线C 的直角坐标方程,得()()22tcos α1tsin α4++=,即2t 2tsin α30+-=,所以1212t t 2t t 3sin α+=-⎧⎨=-⎩,由题意知,不妨设12t 2t =-,所以222t 22t 3sin α-=-⎧⎨-=-⎩,即cos sin αα⎧=⎪⎪⎨⎪=⎪⎩cos sin αα⎧=⎪⎪⎨⎪=⎪⎩,即k =k =所以直线l5y 100-+=5y 100+=. 【点睛】本题主要考查了参数方程与普通方程的互化,以及直线参数方程的应用,其中解答中熟记直线参数方程中参数的几何意义,合理准确计算是解答的关键,着重考查了运算与求解能力,属于基础题. 选修4-5: 不等式选讲23.已知,a b 是正实数,且2a b +=, 证明:2≤;(Ⅱ)33(4)()a b a b ++≥.【答案】(1)见解析;(2)见解析 【解析】 【分析】(1)利用基本不等式证明即可.(2)利用综合法,通过重要不等式证明即可.【详解】()1,a b 是正实数,a b ∴+≥1≤,∴24,a b =++2≤,当且仅当1a b ==时,取"".=()2222,a b ab +≥∴()()22222224a ba b ab a b +≥+=+=∴222,a b +≥∴()()()223443344222224,a b a b a b a b ab a b a b a b ++=+++≥++=+≥当且仅当22,1,a b a b =⎧⎨=⎩即1a b ==时,取"".=【点睛】本题考查不等式的证明,综合法的应用,基本不等式的应用,是基本知识的考查.。
鹤岗市第一中学2019届高三上学期第三次月考英语试题一.单项选择(共20小题;每小题1分,满分20分)从每题所给的A、B、C和D四个选项中,选出最佳选项。
1. Before you start, it seems that the task is _____________ to be accomplished.A. possibleB. unlikelyC. impossibleD. probable2. You are supposed to _____________ the work, but Ihaven’t seen it now.A. have been finishedB. be finishingC. have finishedD. finish3. Unfortunately, fifteen-year-old Paige suffers from _______________ rare brain disease, which affects as few as 12 people in the world, and could kill her any day _______________warning.A. a; withoutB. the; withoutC. a; withD. the; with4. With such a tightschedule, everyone will have to go all out if they_____________ the task.A.have completedB.would completeC.will completeD.are to complete5. I _____________tolook upon life as a process of getting.A. wasbroughtupB. wasbrought inC. wasbrought outD. wasbrought forward6. This happens _____________ the children are in two-parent or one-parent families.A. no matterB. eitherC. ifD. whether7. The orphan enjoyed a pleasant evening in the_____________ of the volunteers.A. accompanyB. companionC. companyD. companionship8. He is a professor, _____________I have been looking forward to becoming.A. whichB. whoC. whomD. that9. He was giving his collection _____________ for free.A. upB. awayC. offD. back10. Greta has always tended to keep her colleagues _____________.A. in a distanceB. in the distanceC. at a distanceD. at the distance11. _____________ you are trying to lose weight to please yourself, it’s going to be tough to keep your motivation level high.A. IfB. WhenC. BecauseD. Unless12. Why not _____________ what you enjoy and do that?A. discoverB. to discover D. discovering D. discovered13. It is a great evening, and definitely _____________ all the hard work.A. worthyB. worthC. worthwhileD. worthless14. The producer comes regularly to collect the cameras _______________ to our shop for quality problems.A. returningB. being returnedC. returnedD. to be returned15. _______________ they got the machine tool repaired.A. At no timeB. In no timeC. At one timeD. In one time16. The way the guests ________ in the hotel influenced their evaluation of the service.A. treatedB. were treatedC. would treatD. would be treated17. The hotel is currently _______________ construction.A. inB. ofC. onD. under18. You can’t _______________ on anybody to keep your secret.A. relyB. trustC. believeD. support19. Some people waste too much water.They don’t believe that it can_____________some day.A. use upB. run out ofC.be run outD.run out20. That’s the way I look at most of _______________ has happened to me.A. thatB. whichC. whatD. all二.阅读理解(共15小题;每小题2分,满分30分)阅读下列短文,从每题所给的A、B、C和D四个选项中,选出最佳选项,并在答题卡上将该项涂黑。
黑龙江省鹤岗一中高三(上)第三次模拟物理试卷一.选择题1.一个小球由静止开始沿斜面下滑,经3 s进入一个水平面,再经6 s停下,斜面与水平面交接处的能量损失不计,则小球在斜面上和水平面上的位移大小之比是( )A. 1∶1B. 1∶2C. 1∶3D. 2∶1【答案】B【解析】在斜面上的初速度为0,末速度为v,在水平面上的初速度为v,末速度为零,故斜面上的加速度和水平面上加速度大小之比为122 1a a =,根据22ax v=可得1212xx=,B正确.2.已知两个力的合力F=10N,其中一个分力F1=16N,则另一个分力F2可能是()A. 1NB. 3NC. 5ND. 7N【答案】D【解析】试题分析:根据两个分力的合力在两个分力之差与两个分力之和之间,分析另一个分力的大小可能值.有两个共点力的合力大小为10N,若其中一个分为大小为16N,另一个分力的大小应在626N F N#范围,所以可能为7N,D正确.3.下列实验中,找到电荷间相互作用规律的实验是()A. 库仑扭秤实验B. 卡文迪许实验C. 密立根油滴实验D. 奥斯特电流磁效应实验【答案】A【解析】库仑利用扭秤装置,研究出两个静止点电荷间的相互作用规律---库仑定律,故A正确;卡文迪许实验测量出了万有引力常量。
故B 错误;密立根通过油滴实验,测出了电子电荷量的精确数值,任何物体带电量的数值都是元电荷电量的整数倍。
故C 错误;奥斯特实验说明了通电导体周围存在磁场,即电流的磁效应,故D 错误。
所以A 正确,BCD 错误。
4.如图所示,在光滑的水平面上有一段长为L 、质量分布均匀的绳子,绳子在水平向左的恒力F 作用下做匀加速直线运动。
绳子上某一点到绳子右端的距离为x ,设该处的张力为T ,则能正确描述T 与x 之间的关系的图象是A. B. C. D.【答案】A 【解析】试题分析:对x 受力分析,对整体受力分析由牛顿第二定律可求得整体的加速度;再由牛顿第二定律可得出T 与x 的关系.设单位长度质量为m ,对整体分析有F Lma =;对x 分析可知T xma =,联立解得:FT x L=,故可知T 与x 成正比,且x=0时,T=0,故A 正确;5.一水平固定的水管,水从管口以不变的速度源源不断地喷出,水管距地面高 1.8h m =,水落地的位置到管口的水平距离 1.2x m =,不计空气及摩擦阻力,水从管口喷出的初速度大小是A. 1.2m/sB. 2.0m/sC. 3.0m/sD. 4.9m/s 【答案】B 【解析】水平喷出的水,运动规律为平抛运动,根据平抛运动规律h =12gt 2可知,水在空中的时间为0.6 s ,根据x =v 0t 可知水平速度为v 0=2.0 m/s.因此选项B 正确. 6.土星与太阳的距离是火星与太阳距离的6倍多。
鹤岗一中高三学年12月月考英语试题一.单项选择(共20小题;每小题1分,满分20分)从每题所给的A、B、C 和D四个选项中,选出最佳选项。
1. Before you start, it seems that the task is _____________ to be accomplished.A. possibleB. unlikelyC. impossibleD. probable2. You are supposed to _____________ the work, but I haven’tseen it now.A. have been finishedB. be finishingC. have finishedD. finish3. Unfortunately, fifteen-year-old Paige suffers from _______________ rare brain disease, which affects as few as 12 people in the world, andcould kill her any day _______________ warning.A. a; withoutB. the; withoutC. a; withD. the; with4. With such a tight schedule, everyone will have to go all out if they_____________ the task.A. have completedB. would completeC. will completeD. are to complete5. I _____________ to look upon life as a process of getting.A. was brought upB. was brought inC. was brought outD. was brought forward6. This happens _____________ the children are in two-parent or one-parent families.A. no matterB. eitherC. ifD. whether7. The orphan enjoyed a pleasant evening in the _____________ of the volunteers.A. accompanyB. companionC. companyD. companionship8. He is a professor, _____________ I have been looking forward tobecoming.A. whichB. whoC. whomD. that9. He was giving his collection _____________ for free.A. upB. awayC. offD. back10. Greta has always tended to keep her colleagues _____________.A. in a distanceB. in the distanceC. at a distanceD. at the distance11. _____________ you are trying to lose weight to please yourself, it’s going to be tough to keep your motivation level high.A. IfB. WhenC. BecauseD. Unless12. Why not _____________ what you enjoy and do that?A. discoverB. to discover D. discovering D. discovered13. It is a great evening, and definitely _____________ all the hard work.A. worthyB. worthC. worthwhileD. worthless14. The producer comes regularly to collect the cameras _______________ to our shop for quality problems.A. returningB. being returnedC. returnedD. to be returned15. _______________ they got the machine tool repaired.A. At no timeB. In no timeC. At one timeD. In one time16. The way the guests ________ in the hotel influenced their evaluationof the service.A. treatedB. were treatedC. would treatD. would be treated17. The hotel is currently _______________ construction.A. inB. ofC. onD. under18. You can’t _______________ on anybody to keep your secret.A. relyB. trustC. believeD. support。
黑龙江省鹤岗市第一中学高三上学期第三次月考语文试题一、现代文阅读(36分)(一)论述类文本阅读(本题共3小题,9分)阅读下面的文字,完成1-3题为什么梅花能够与人格如此胶合为一体呢?因为梅花的形象特征与某种道德评价的思想价值完全吻合。
首先是梅花的色淡气清。
清淡是对浓艳的否定。
浓艳为俗,清淡超俗、高雅。
而高雅脱俗,是文人学士所追求的风格,所标榜的气度。
宋熊禾《涌翠亭梅花》言:“此花不必相香色,凛凛大节何峥嵘!”梅花之神,在峥嵘之“大节”,而不在表面之“香色”。
放翁《梅》诗也说:“逢时决非桃李辈,得道自保冰雪颜。
”颜色的清淡正与高士之“得道”契合了。
其次是梅姿的疏影瘦身。
戴禺说:“精神全向疏中足,标格端于瘦处真。
”梅花之影疏,显露出人的一种雅趣;而梅花之瘦姿,则凸现了人的一种倔强,因而是人格坚贞不屈的象征。
清恽寿平《梅图》说:“古梅如高士,坚贞骨不媚。
”顽劲的树干,横斜不羁的枝条,历经沧桑而铸就的苍皮,是士人那种坚韧不拔、艰苦奋斗,决不向压迫他、摧残他的恶劣环境作丝毫妥协的人格力量和斗争精神的象征。
也正因为梅花具有此种不屈的品格,它才冲寒而发。
为了将美好的春天的信息,尽早报告给人间,梅花心甘情愿被雪礼葬,在所不惜:“一朵忽先变,百花皆后香。
为传春消息,不惜雪埋藏。
”这种伟大的人格力量,真可感天地,泣鬼神!再次是梅花的景物陪衬。
梅花色淡,姿瘦,神韵高雅,而配合其环境的是月光、烟影、竹篱、苍松、清水和寒雪,这就从各个角度全方位地烘托出梅花的“高标逸韵”,收到相得益彰的艺术效果。
宋杨无咎《柳梢青》云:“雪月光中,烟溪影里,松竹梢头。
”这就是梅花的陪村意象群:寒雪、淡月、清流、薄(疏)雾、劲松、瘦竹。
其清一贯,其骨相通。
张道洽《梅花》诗云:“雅淡久无兰作伴,孤高惟有竹为朋。
”梅品之“雅淡”,梅格之“孤高”,惟有虚心、有节、耐寒、清淡的竹是它的友朋,诠释了陪衬的艺术力量。
唐朱庆余《早梅》诗更是将雪、露、松、竹与梅并在一起写,让人们受到最清幽、最高雅的浑融境界的视觉冲击:“天然根性异,万物尽难陪。
好教育云平台 名校精编卷 第1页(共4页) 好教育云平台 名校精编卷 第2页(共4页)2019届黑龙江省鹤岗市第一中学 高三上学期第三次月考数学(理)试题数学注意事项:1.答题前,先将自己的姓名、准考证号填写在试题卷和答题卡上,并将准考证号条形码粘贴在答题卡上的指定位置。
2.选择题的作答:每小题选出答案后,用2B 铅笔把答题卡上对应题目的答案标号涂黑,写在试题卷、草稿纸和答题卡上的非答题区域均无效。
3.非选择题的作答:用签字笔直接答在答题卡上对应的答题区域内。
写在试题卷、草稿纸和答题卡上的非答题区域均无效。
4.考试结束后,请将本试题卷和答题卡一并上交。
一、单选题 1.复数z=2−1+i ,则A .Z 的虚部为-1B .Z 的实部为1C .|Z |=2D .Z 的共轭复数为1+i2.已知集合A ={x||x|≤3},集合B ={x|y =lg(a −x),且x ∈N},若集合A ∩B ={0,1,2},则实数a 的取值范围是A .[2,4]B .[2,4)C .(2,3]D .[2,3]3.已知函数f (x )的定义域为[0,2],则函数g (x )=f (12x)+√8−2x 的定义域为A .[0,3]B .[0,2]C .[1,2]D .[1,3]4.执行如下所示的程序框图,如果输入t ∈[−1,2],则输出的s 属于A .[1,4]B .[12,1) C .[12,1] D .[12,4]5.在四棱锥P −ABCD 中,PA ⊥底面ABCD ,底面ABCD 为正方形,PA =AB ,该四棱锥被一平面截去一部分后,剩余部分的三视图如图,则截去部分体积与剩余部分体积的比值为A .12 B .13 C .14 D .156.若点M(x,kx −2)满足不等式组{x ≥−1x −y ≤0x +y ≤4 ,则k 的取值范围为A .(−∞,−1]∪[2,+∞)B .[−1,2]C .(−∞,−7]∪[2,+∞)D .[−7,2]7.将函数g(x)=2cos 2(x +π6)−1的图象,向右平移π4个单位长度,再把纵坐标伸长到原来的2倍,得到函数f(x),则下列说法正确的是A .函数f(x)的最小正周期为2πB .函数f(x)在区间[7π12,5π4]上单调递增C .函数f(x)在区间[2π3,5π4]上的最小值为−√3 D .x =π3是函数f(x)的一条对称轴8.在棱长为1的正方体中ABCD −A 1B 1C 1D 1,点P 在线段AD 1上运动,则下列命题错误的是A .异面直线C 1P 和CB 1所成的角为定值 B .直线CD 和平面BPC 1平行C .三棱锥D −BPC 1的体积为定值 D .直线CP 和平面ABC 1D 1所成的角为定值 9.已知正数数列{a n }是公比不等于1的等比数列,且lga 1+lga 2019=0,若f(x)=21+x 2,则f(a 1)+f(a 2)+⋯+f(a 2019)=A .2018B .4036C .2019D .403810.ΔABC 中,角A 、B 、C 所对的边分别为a 、b 、c ,且满足a =4,asinB =√3bcosA ,则ΔABC 面积的最大值是A .4√3B .2√3C .8√3D .4此卷只装订不密封班级 姓名 准考证号 考场号 座位号好教育云平台 名校精编卷 第3页(共4页) 好教育云平台 名校精编卷 第4页(共4页)11.已知(){}|0M f αα==, (){}|0N g ββ==,若存在,M N αβ∈∈,使得n αβ-<,则称函数()f x 与()g x 互为“n 度零点函数”.若()231xf x -=-与()2xg x x ae =-互为“1度零点函数”,则实数a 的取值范围为A .214(,e e ⎤⎥⎦B .214(, e e ⎤⎥⎦C .242[, e e ⎫⎪⎭D .3242[, e e ⎫⎪⎭二、填空题12.在直角梯形ABCD 中,AD//BC ,∠ABC =900,AB =BC =4,AD =2,则向量BD ⃑⃑⃑⃑⃑⃑ 在向量AC ⃑⃑⃑⃑⃑ 上的投影为_______.13.已知向量a 与b 的夹角是3π,且1,2a b ==,若()3a b a λ+⊥,则实数λ=__________.14.甲、乙、丙三人玩摸卡片游戏,现有标号为1到12的卡片共12张,每人摸4张。
黑龙江省鹤岗市第一中学2019届高三英语上学期第三次月考试题(含解析)一.单项选择(共20小题;每小题1分,满分20分)从每题所给的A、B、C和D四个选项中,选出最佳选项.1.Before you start, it seems that the task is _____________ to be accomplished。
A. possible B。
unlikelyC。
impossible D。
probable【答案】B【解析】【详解】考查形容词辨析及固定短语。
句意:在你开始之前,似乎这个任务是不可能被完成的。
形容词短语be likely/unlikely to do sth可能/不可能做某事,该短语的主语可以是人也可以是物;AD项与句意不符,impossible的主语通常都是it。
故B项正确。
2.You are supposed to _____________ the work, but I haven’t seen it now。
A。
have been finished B. be finishingC. have finished D。
finish【答案】C【解析】【详解】考查虚拟语气.句意:你本应该已经完成这个工作了,但是我现在还没有看到。
固定搭配be supposed to have done sth本应该做了某事,实际上却没有做。
故C项正确.3.Unfortunately, fifteen—year—old Paige suffers from _______________ rare brain disease, which affects as few as 12 people in the world, and could kill her any day _______________ warning.A。
a; without B。
the; withoutC. a; withD. the; with【答案】A【解析】【详解】考查冠词和句意理解.句意:不幸的是,15岁的Paige患上了一种罕见的脑部疾病,这种病只影响了全世界12人,任何一天都可以没有任何警告就杀死她。
鹤岗市第一中学2019届高三上学期第三次月考英语试题一.单项选择(共20小题;每小题1分,满分20分)从每题所给的A、B、C和D四个选项中,选出最佳选项。
1. Before you start, it seems that the task is _____________ to be accomplished.A. possibleB. unlikelyC. impossibleD. probable2. You are supposed to _____________ the work, but Ihaven’t seen it now.A. have been finishedB. be finishingC. have finishedD. finish3. Unfortunately, fifteen-year-old Paige suffers from _______________ rare brain disease, which affects as few as 12 people in the world, and could kill her any day _______________warning.A. a; withoutB. the; withoutC. a; withD. the; with4. With such a tightschedule, everyone will have to go all out if they_____________ the task.A.have completedB.would completeC.will completeD.are to complete5. I _____________tolook upon life as a process of getting.A. wasbroughtupB. wasbrought inC. wasbrought outD. wasbrought forward6. This happens _____________ the children are in two-parent or one-parent families.A. no matterB. eitherC. ifD. whether7. The orphan enjoyed a pleasant evening in the_____________ of the volunteers.A. accompanyB. companionC. companyD. companionship8. He is a professor, _____________I have been looking forward to becoming.A. whichB. whoC. whomD. that9. He was giving his collection _____________ for free.A. upB. awayC. offD. back10. Greta has always tended to keep her colleagues _____________.A. in a distanceB. in the distanceC. at a distanceD. at the distance11. _____________ you are trying to lose weight to please yourself, it’s going to be tough to keep your motivation level high.A. IfB. WhenC. BecauseD. Unless12. Why not _____________ what you enjoy and do that?A. discoverB. to discover D. discovering D. discovered13. It is a great evening, and definitely _____________ all the hard work.A. worthyB. worthC. worthwhileD. worthless14. The producer comes regularly to collect the cameras _______________ to our shop for quality problems.A. returningB. being returnedC. returnedD. to be returned15. _______________ they got the machine tool repaired.A. At no timeB. In no timeC. At one timeD. In one time16. The way the guests ________ in the hotel influenced their evaluation of the service.A. treatedB. were treatedC. would treatD. would be treated17. The hotel is currently _______________ construction.A. inB. ofC. onD. under18. You can’t _______________ on anybody to keep your secret.A. relyB. trustC. believeD. support19. Some people waste too much water.They don’t believe that it can_____________some day.A. use upB. run out ofC.be run outD.run out20. That’s the way I look at most of _______________ has happened to me.A. thatB. whichC. whatD. all二.阅读理解(共15小题;每小题2分,满分30分)阅读下列短文,从每题所给的A、B、C和D四个选项中,选出最佳选项,并在答题卡上将该项涂黑。
鹤岗市第一中学2019届高三上学期第三次月考英语试题一.单项选择(共20小题;每小题1分,满分20分)从每题所给的A、B、C和D四个选项中,选出最佳选项。
1. Before you start, it seems that the task is _____________ to be accomplished.A. possibleB. unlikelyC. impossibleD. probable2. You are supposed to _____________ the work, but I haven’t seen it now.A. have been finishedB. be finishingC. have finishedD. finish3. Unfortunately, fifteen-year-old Paige suffers from _______________ rare brain disease, which affects as few as 12 people in the world, and could kill her any day _______________ warning.A. a; withoutB. the; withoutC. a; withD. the; with4. With such a tight schedule, everyone will have to go all out if they _____________the task.A. have completedB. would completeC. will completeD. are to complete5. I _____________ to look upon life as a process of getting.A. was brought upB. was brought inC. was brought outD. was brought forward6. This happens _____________ the children are in two-parent or one-parent families.A. no matterB. eitherC. ifD. whether7. The orphan enjoyed a pleasant evening in the _____________ of the volunteers.A. accompanyB. companionC. companyD. companionship8. He is a professor, _____________ I have been looking forward to becoming.A. whichB. whoC. whomD. that9. He was giving his collection _____________ for free.A. upB. awayC. offD. back10. Greta has always tended to keep her colleagues _____________.A. in a distanceB. in the distanceC. at a distanceD. at the distance11. _____________ you are trying to lose weight to please yourself, it’s going to be tough to keep your motivation level high.A. IfB. WhenC. BecauseD. Unless12. Why not _____________ what you enjoy and do that?A. discoverB. to discover D. discovering D. discovered13. It is a great evening, and definitely _____________ all the hard work.A. worthyB. worthC. worthwhileD. worthless14. The producer comes regularly to collect the cameras _______________ to our shop for quality problems.A. returningB. being returnedC. returnedD. to be returned15. _______________ they got the machine tool repaired.A. At no timeB. In no timeC. At one timeD. In one time16. The way the guests ________ in the hotel influenced their evaluation of the service.A. treatedB. were treatedC. would treatD. would be treated17. The hotel is currently _______________ construction.A. inB. ofC. onD. under18. You can’t _______________ on anybody to keep your secret.A. relyB. trustC. believeD. support19. Some people waste too much water. They don’t believe that it can_____________ some day.A. use upB. run out ofC. be run outD. run out20. That’s the way I look at most of _______________ has happened to me.A. thatB. whichC. whatD. all二.阅读理解(共15小题;每小题2分,满分30分)阅读下列短文,从每题所给的A、B、C和D四个选项中,选出最佳选项,并在答题卡上将该项涂黑。