2020届全国100所名校最新高考模拟示范卷 英语卷(二)PDF版有答案

合集下载

全国ⅰ卷地区2020届高三英语试卷汇编:书面表达

全国ⅰ卷地区2020届高三英语试卷汇编:书面表达

书面表达河北衡水中学2020届全国高三第一次联合考试第二节书面表达(满分25分)假定你是李华.给你开网店的英国朋友peter寄去了一包自家产的有机(organic)绿茶,并附有一份该茶的说明。

请你给peter发封邮件,要点如下:1.请他品茶;2.说明该茶的特点(有机、绿色等);3.请他帮忙代卖该茶。

注意:1.词数100左右;2.可以适当增加细节,以使行文连贯;3.开头语和结尾语已为你写好。

第二节书面表达Dear PeterHow are you? I hope you and your family are quite wellYesterday I posted a package of tea to you, inside which is a description for it. Our family plant tea and we make the tea product by ourselves. Green and organic, the tea is rich in nutrition like vitamins. You can taste it and will find how nice it is. Meanwhile, I'd like to ask you a favor. I wonder if you could sell the tea for me in your shop. Thank you for your help!Looking forward to your reply .Yours ,Li Hua邢台市2019-2020学年高三上学期第二次月考英语试卷第二节书面表达(满分25分)假定你是李华,你校将举办“中国古典名著研讨会”活动。

请用英文给喜欢中国文学的外教Smith写一封电子邮件,邀请他参加该活动。

内容包括:1.活动时间和地点;2.活动目的:走进中国古典文学,感受中国传统文化;3.活动内容:探讨名家,交流阅读经验。

2020届全国100所名校高考模拟金典卷(四)数学(理)试题及答案

2020届全国100所名校高考模拟金典卷(四)数学(理)试题及答案

绝密★启用前2020届全国100所名校高考模拟金典卷(四)数学(理)试题注意事项:1、答题前填写好自己的姓名、班级、考号等信息2、请将答案正确填写在答题卡上 一、单选题 1.已知集合,,则() A .B .C .D .答案:C先求出集合B ,再利用交集定义和并集定义能求出结果. 解: 由得x >0,所以B ={x|x >0}.所以A ∩B ={x|0<x<1}.,故选:C . 点评:本题考查交集、并集的求法及应用,涉及指数函数单调性的应用,是基础题. 2.若复数1z ii=+(i 为虚数单位),则z z ⋅=() A .12i B .12 C .14D .14-答案:B化简可得z ,而2z z z ⋅=,计算模长即可. 解:∵1i 1111i 2i i i z i i -+===++-()()(), ∴211142z z z +⋅=== 故选B . 点评:本题考查复数的代数形式的运算,涉及模长的求解,属于基础题.3.袋子中装有大小、形状完全相同的2个白球和2个红球,现从中不放回地摸取两个球,已知第二次摸到的红球,则第一次摸到红球的概率为() A .16B .13C .12D .15答案:B由题意,分别列出第二次摸到的红球的所有可能结果和第一次摸到红球的事件,利用古典概型计算公式确定去概率值即可. 解:设两个红球为12,R R ,两个白球为12,w w ,则第二次摸到的红球的所有可能结果为:112121122212,,,,,w R w R R R w R w R R R 共6种, 其中第一次摸到红球的事件包括:2112,R R R R 共2种, 结合排列组合公式可知第一次摸到红球的概率为2163P . 点评:本题主要考查古典概型计算公式及其应用等知识,意在考查学生的转化能力和计算求解能力.4.已知角θ的终边经过点5,62P ⎛⎫-- ⎪⎝⎭,则tan 4πθ⎛⎫+= ⎪⎝⎭()A .76-B .177-C .2-D答案:B由已知可得tan θ,再由两角和的正切公式,即可求解. 解:角θ的终边经过点5612,6,tan 5252P θ-⎛⎫--∴==⎪⎝⎭-, 所以tan tan174tan 471tan tan 4πθπθπθ+⎛⎫+==- ⎪⎝⎭-. 故选:B. 点评:本题考查三角函数定义的应用、三角恒等变换,考查数学运算能力,属于基础题.5.若函数()21,01,0x x f x mx m x ⎧+≥=⎨+-<⎩,在其定义域上单调递增,则实数m 的取值范围是() A .(]0,3B .()0,3C .[)3,+∞D .[)0,+∞答案:A分段函数()f x 两段均为单调递增,而且右段的最低点不低于左段的最高点,即可求解. 解:函数()21,01,0x x f x mx m x ⎧+≥=⎨+-<⎩在(),-∞+∞上单调递增,01212m m >⎧∴⎨-≤+=⎩,解得03m <≤, ∴实数m 的取值范围是(]0,3.故选:A. 点评:本题考查分段函数的单调性,要注意分段函数各段单调性相同的区间合并的条件,属于基础题.6.已知双曲线22:41C x y -=,经点()2,0P 的直线l 与C 有唯一公共点,则直线l 的方程为() A .21y x =- B .112y x =-+ C .112y x =-或112y x =-+ D .21y x =-或112y x =-+ 答案:C点P 在双曲线内,过点()2,0P 的直线l 与C 有唯一公共点,则直线l 与渐近线平行,即可求解. 解:由双曲线的几何性质可知,当直线与渐近线平行时, 直线l 与C 有唯一公共点,由于双曲线的渐近线为12y x =±, 故直线l 的方程为()122y x =-或()122y x =--, 即112y x =-或112y x =-+.故选:C. 点评:本题考查双曲线的性质以及直线与双曲线的位置关系,考查数形结合思想,属于基础题. 7.在ABC 中,角A ,B 的对边分别是a ,b ,且60A =︒,2b =,a x =,若解此三角形有两解,则x 的取值范围是()A .x >B .02x <<C 2x <<D 2x <≤答案:C由三角形有两解可得,6090B ︒<<︒或90120B ︒<<︒,得到sin B 的取值范围,再由正弦定理,即可求解. 解:由正弦定理得sin sin b A B a ==,60A =︒,0120B ∴︒<<︒,要使此三角形有两解,则60120B ︒<<︒,且90B ≠︒sin 1B <<,1<<2x <<. 故选:C. 点评:本题考查正弦定理解三角形,确定角的范围是解题的关系,考查数学运算能力,属于基础题.8.二项式431(2)3nx x-的展开式中含有非零常数项,则正整数n 的最小值为() A .7 B .12C .14D .5答案:A试题分析:展开式的通项为471123rn r r n rr n T C x--+⎛⎫=- ⎪⎝⎭,令470n r -=,据题意此方程有解,74rn ∴=,当4r =时,n 最小为7,故选A. 【考点】二项式定理的应用.9.榫卯(s ǔnm ǎo )是两个木构件上所采用的一种凹凸结合的连接方式.凸出部分叫榫,凹进去的部分叫卯,榫和卯咬合,起到连接作用.代表建筑有北京的紫禁城、天坛祈年殿,山西悬空寺等,如图是一种榫卯构件中榫的三视图,则该榫的表面积和体积为()A .8+162+8ππ,B .9+1628ππ+,C .8+1648ππ+,D .9+1648ππ+,答案:A由三视图得到组合体的直观图,然后再根据组合体的组合形式及题中数据求出表面积和体积. 解:由三视图知该榫头是由上下两部分构成:上方为长方体(底面为边长是1的正方形,高为2),下方为圆柱(底面圆半径为2,高为2). 其表面积为圆柱的表面积加上长方体的侧面积, 所以()()()222222412816S πππ=⨯⨯+⨯⨯+⨯=+.其体积圆柱与长方体体积之和,所以()2221128+2V ππ=⨯⨯+⨯⨯=. 故选A . 点评:解答本题的关键是由三视图得到组合体的形状,容易出现的错误是求表面积时忽视圆柱和长方体相连的部分的面积,考查空间想象力和计算能力,属于基础题. 10.运行程序框图,如果输入某个正数后,输出的,那么的值为()A.3 B.4 C.5 D.6答案:B依次运行框图中给出的程序,根据输出结果所在的范围来判断图中的值.解:依次运行框图中的程序,可得:第一次:;第二次:;第三次:;第四次:;第五次:;……因为输出的,所以程序运行完第四次即可满足题意,所以判断框中的值为4.故选B.点评:程序框图的补全及逆向求解问题思路:①先假设参数的判断条件满足或不满足;②运行循环结构,一直到运行结果与题目要求的输出结果相同为止;③根据此时各个变量的值,补全程序框图.此类试题要求学生要有比较扎实的算法初步的基本知识,以及综合分析问题和解决问题的能力,要求较高,属中档题.11.已知定义在非零实数集上的奇函数,函数与图像共有4个交点,则该4个交点横坐标之和为()A.2 B.4 C.6 D.8答案:D 先由函数是奇函数,得到的对称中心,再根据得到的对称中心,由对称性,即可得出结果.解: 因为函数是奇函数,关于点中心对称;所以函数关于点中心对称; 又由得到,即函数的对称中心为,因此,点也是函数的一个对称中心; 由函数与图像共有4个交点, 交点横坐标依次设为且, 所以由函数对称性可知,,因此.故选D 点评:本题主要考查函数对称性、以及奇偶性的应用,熟记概念以及三角函数性质,即可求解,属于常考题型.12.已知函数()xf x ax e k =--,若21,k e ⎡⎤∈-⎣⎦时,函数()f x 至少有2个零点,其中e 为自然对数的底数,则实数a 的取值范围是() A .()2,e +∞ B .()1,+∞C .()21,eD .()0,1答案:A由()0f x =,得2,1,x ax e k k e ⎡⎤-=∈-⎣⎦,令()x g x ax e ,转化为()g x 与y k =,21,k e ⎡⎤∈-⎣⎦至少有两交点,求出()g x 的单调性,极值最值,结合函数变换趋势,建立k 的不等量关系,即可求解.解:由题意可知方程x ax e k -=,21,k e ⎡⎤∈-⎣⎦上至少有两个实数根,令()x g x ax e ,则()g x 与2,1,y k k e ⎡⎤=∈-⎣⎦至少有两交点,()x g x a e '=-,当0,()0a g x ≤'<在R 恒成立, ()g x ∴在R 上单调递减,()g x 与2,1,y k k e ⎡⎤=∈-⎣⎦至多只有一个交点,不合题意;当0a >时,ln ,()0.ln ,()0x a g x x a g x <'>>'<,()g x 的单调递增区间是(,ln )a -∞,单调递减区间是(ln ,)a +∞,所以ln x a =时,()g x 取得极大值,也是最大值为ln a a a -, 当,(),,()x g x x g x →-∞→-∞→+∞→-∞,要使()g x 与2,1,y k k e ⎡⎤=∈-⎣⎦至少有两交点,只需2ln a a a e ->,ln (ln 1),0,ln 0,,ln 0a a a a a a e a a a a e a a a -=-<≤-≤>->,而2ln a a a e ->,a e ∴>,设()ln ,,()ln 0h a a a a a e h a a =->'=>()h a ∴在(,)e +∞是单调递增,而22()h e e =, 2ln a a a e ∴->的解为2a e >,a ∴的取值范围是()2,e +∞.故选:A. 点评:本题考查零点问题与函数交点的关系,利用导数研究函数的性质是解题的关键,考査分类讨论思想和数学运算、逻辑推理能力,属于较难题.. 二、填空题13.已知a 、b 为两个单位向量,且0a b ⋅=,则a 与2a b +夹角的余弦值为__________.. 先求出复数2a b +的模,再由向量夹角公式,即可求出结果. 解:因为a 、b 为两个单位向量,且0a b ⋅=,所以22(2)14a b a b +=+=+=设a 与2a b +夹角为θ,则22(2)cos2a b aa b aa a bθ+•+•====+点评:本题主要考查求向量的夹角,熟记平面向量数量积的运算以及夹角公式即可,属于常考题型.14.椭圆22(0)167x ym m+=>的离心率为_________.答案:34由椭圆方程得到,,a b c,直接计算离心率即可.解:因为椭圆22(0)167xym m+=>,所以22216,79a mb mc m===,.所以34cc ea====,故答案为:34点评:本题主要考查椭圆的标准方程,椭圆的离心率,考查数学运算能力,属于容易题.15.已知,x y∈R,满足20,250,470,x yx yx y--≤⎧⎪+-≥⎨⎪-+≥⎩则4z y x=-的最大值为__________.答案:2-做出满足条件的可行域,根据图形求出目标函数的最值.解:由约束条件20250470x yx yx y--≤⎧⎪+-≥⎨⎪-+≥⎩做出可行域如图(阴影部分)所示,当目标函数4z y x=-过点A时,取得最大值,由250470x y x y +-=⎧⎨-+=⎩,得()1,2A ,所以max 242z =-=-. 故答案为:2-.点评:本题考查二元一次不等式组表示平面区域,利用数形结合求线性目标函数的最值,属于基础题.16.如图,在直角梯形ABCD 中,90ABC ∠=︒,2CD =,1AB BC ==,E 是边CD 的中点,ADE 沿AE 翻折成四棱锥D ABCE '-,则点C 到平面ABD '距离的最大值为__________.答案:22由已知得CE平面ABD ',直线CE 上任一点到平面ABD '距离都相等,转化过CE 上任一点作与平面ABD '垂直的平面,根据面面垂直的性质定理,做出点到平面距离的线段,求出长度关系,进而求出其最大值. 解:由翻折过程可得,在如图所示的四棱锥D ABCE '-中, 底面ABCE 为边长是1的正方形,侧面D EA '中,D E AE '⊥,且1D E AE '==,AE D E '⊥,AE CE ⊥,D E CE E '=,AE ∴⊥平面D CE ',作D M CE '⊥于M ,作MN AB ⊥于N ,连接D N ', 则由AE ⊥平面D CE ',可得D MAE '⊥,CE AE E =D M '∴⊥平面ABCE .又AB ⊂平面ABCE ,D M AB '∴⊥,MN AB ⊥,D MMN M '=,AB ∴⊥平面D MN '.AB ⊂平面ABD ',∴平面ABD '⊥平面D MN ',平面ABD '平面D MN D N ''=,在D MN '△中,作MH D N '⊥于H ,则MH ⊥平面ABD ',,ABCE AB ⊂平面ABD ',CE ⊄平面ABD ',CE ∴∥平面ABD ',MH ∴即为点C 到平面ABD '的距离,在Rt D MN '△中,D M MN '⊥,1MN =, 设D M x '=,则01x D E '<≤=,21D N x '∴=+. 由D M MN D N MH ''⋅=⋅可得21x x MH =+⋅,2222111MH x x ∴==≤++,当1x =时等号成立,此时D E '⊥平面ABCE ,综上可得,点C 到平面ABD '距离的最大值为22. 故答案为:22. 点评:本题考查空间线、面的位置关系,利用基本不等式解决点到面的距离最大问题,注意空间垂直关系的相互转化,做出点面距是解题的关键,属于中档题. 三、解答题17.已知数列{}n a 的前n 项和为n S ,数列n S n ⎧⎫⎨⎬⎩⎭是首项为1,公差为2的等差数列.(1)求数列{}n a 的通项公式;(2)设数列{}n b 满足()121215452nn n a a an b b b ⎛⎫+++=-+ ⎪⎝⎭,求数列{}n b 的前n 项和n T .答案:(1)43n a n =-;(2)122n n T +=-.分析:(1)利用1,1,2n n n n S n a S S n -=⎧=⎨-≥⎩进行求解;(2)利用类似1,1,2n n nn S n a S S n -=⎧=⎨-≥⎩的方法求出nna b ,进而求出n b ,再利用等比数列的求和公式进行求解. 详解:(1)由题意得:21nS n n=-, 当2n ≥时,143n n n a S S n -=-=-,1n =时,11a =对上式也成立,∴43n a n =-.(2)()121215452nn n a a a n b b b ⎛⎫+++=-+ ⎪⎝⎭, 当2n ≥时,()111212115412n n n a a an b b b ---⎛⎫+++=-+ ⎪⎝⎭,相减可得:()1432nn n a n b ⎛⎫=- ⎪⎝⎭,又43n a n =-,解得2nn b =,1n =时,12b =对上式也成立,∴2nn b =,∴()12122212n n nT +-==--,∴数列{}n b 的前n 项和122n n T +=-.点睛:利用数列{}n a 的通项公式n a 和前n 项和公式n S 的关系求通项时,要注意1,1,2n n nn S n a S S n -=⎧=⎨-≥⎩为分段函数,解题时容易忽视验证“1n =”的通项是否满足2n ≥的通项.18.在四棱锥AB 中,PA ⊥平面ABCD ,ABC ∆是正三角形,AC 与BD 的交点M 恰好是AC 中点,又4PA AB ==,CDA 120︒∠=.(1)求证:BD PC ⊥;(2)设E 为PC 的中点,点F 在线段AB 上,若直线EF //平面PAD ,求AF 的长; (3)求二面角A PC B --的余弦值. 答案:(1)见解析;(2)1;(3)7. (1)利用线面垂直的判定定理,证明BD ⊥平面PAC ,可得BD ⊥PC ;(2)取DC 中点G ,连接FG ,证明平面EFG ∥平面PAD ,可得FG ∥平面PAD ,证明三角形AMF 为直角三角形,即可求AF 的长;(3)建立空间直角坐标系,求出平面PAC 、平面PBC 的法向量,利用向量的夹角公式,即可求二面角A ﹣PC ﹣B 的余弦值. 解:(1)∵ABC ∆是正三角形,M 是AC 中点, ∴BM AC ⊥,即BD AC ⊥.又∵PA ⊥平面ABCD ,∴PA BD ⊥. 又PA AC A ⋂=,∴BD ⊥平面PAC . ∴BD PC ⊥.(2)取DC 中点G ,连接FG ,则EG //平面PAD ,又直线EF //平面PAD ,EG ∩EF=E,所以平面EFG //平面PAD ,所以FG //AD∵M 为AC 中点,DM AC ⊥,∴AD CD =.∵ADC 120︒∠=,AB 4=,∴BAD BAC CAD 90︒∠=∠+∠=,则三角形AMF 为直角三角形,又60AMF ︒∠=,故AF 1=(3)分别以AB ,AD ,AP 为x 轴,y 轴,z 轴建立如图的空间直角坐标系,∴()B 4,0,0,()C 2,23,0,43D 0,,0⎛⎫⎪ ⎪⎝⎭,()P 0,0,4.434,,0DB ⎛⎫=- ⎪ ⎪⎝⎭为平面PAC 的法向量. ()2,23,4PC =-,()4,0,4PB =-.设平面PBC 的一个法向量为()n x,y,z =,则00n PC n PB ⎧⋅=⎪⎨⋅=⎪⎩,即22340440x y z x z ⎧+-=⎪⎨-=⎪⎩,令3z =,得x 3=,3y =,则平面PBC 的一个法向量为()3,3,3n =,设二面角A PC B --的大小为θ,则7cos ||n PB n PB θ⋅==⋅.所以二面角A PC B --余弦值为7.点评:本题考查线面垂直的判定定理与性质,考查二面角,考查学生分析解决问题的能力,考查向量法的运用,确定平面的法向量是关键.19.已知抛物线()2:20C y px p =>上一点()0,2P x 到焦点F 的距离02PF x =.(1)求抛物线C 的方程;(2)过点P 引圆()(222:30M x y rr -+=<≤的两条切线PA PB 、,切线PA PB 、与抛物线C 的另一交点分别为A B 、,线段AB 中点的横坐标记为t ,求t 的取值范围.答案:(1)24y x =(2)见解析(1)由题意确定p 的值即可确定抛物线方程;(2)很明显切线斜率存在,由圆心到直线的距离等于半径可得12,k k 是方程()2224840rk k r --+-=的两根,联立直线方程与抛物线方程可得点D 的横坐标()()201212223x k k k k =+-+-.结合韦达定理将原问题转化为求解函数的值域的问题即可. 解:(1)由抛物线定义,得02pPF x =+,由题意得: 00022240p x x px p ⎧=+⎪⎪=⎨⎪>⎪⎩解得021p x =⎧⎨=⎩ 所以,抛物线的方程为24y x =.(2)由题意知,过P 引圆()2223(0x y r r -+=<≤的切线斜率存在,设切线PA的方程为()112y k x =-+,则圆心M 到切线PA的距离d r ==,整理得,()222114840rk k r --+-=.设切线PB 的方程为()212y k x =-+,同理可得()222224840r k k r --+-=.所以,12,k k 是方程()2224840r k k r --+-=的两根,121228,14k k k k r +==-. 设()11,A x y ,()22,B x y 由()12124y k x y x⎧=-+⎨=⎩得,2114480k y y k --+=,由韦达定理知,111842k y k -=,所以11211424242k y k k k -==-=-,同理可得2142y k =-.设点D 的横坐标为0x ,则()()222221121204242288k k x x y y x -+-++=== ()()()()22212121212221223k k k k k k k k =+-++=+-+-.设12t k k =+,则[)284,24t r =∈---, 所以,20223x t t =--,对称轴122t =>-,所以0937x <≤点评:本题主要考查抛物线方程的求解,直线与抛物线的位置关系等知识,意在考查学生的转化能力和计算求解能力.20.交强险是车主必须为机动车购买的险种,若普通6座以下私家车投保交强险第一年的费用(基准保费)统一为a 元,在下一年续保时,实行的是费率浮动机制,保费与上一年度车辆发生道路交通事故的情况相联系,发生交通事故的次数越多,费率也就越高,具体浮动情况如下表:某机构为了解某一品牌普通6座以下私家车的投保情况,随机抽取了60辆车龄已满三年的该品牌同型号私家车的下一年续保时的情况,统计得到了下面的表格:以这60辆该品牌车的投保类型的频率代替一辆车投保类型的概率,完成下列问题: (1)按照我国《机动车交通事故责任强制保险条例》汽车交强险价格的规定,950a =,记x 为某同学家的一辆该品牌车在第四年续保时的费用,求x 的分布列与数学期望;(数学期望值保留到个位数字)(2)某二手车销售商专门销售这一品牌的二手车,且将下一年的交强险保费高于基本保费的车辆记为事故车,假设购进一辆事故车亏损5000元,一辆非事故车盈利10000元:①若该销售商购进三辆(车龄已满三年)该品牌二手车,求这三辆车中至多有一辆事故车的概率;②若该销售商一次购进100辆(车龄已满三年)该品牌二手车,求他获得利润的期望值. 答案:(1)分布列见解析,942EX ≈(2)①2027,②50万元 (1)由题意列出X 的可能取值为0.9a ,0.8a ,0.7a ,a ,1.1a ,1.3a ,结合表格写出概率及分布列,再求解期望(2)①建立二项分布求解三辆车中至多有一辆事故车的概率 ②先求出一辆二手车利润的期望,再乘以100即可 解:(1)由题意可知:X 的可能取值为0.9a ,0.8a ,0.7a ,a ,1.1a ,1.3a 由统计数据可知:1(0.9)6P X a ==,1(0.8)12P X a ==,1(0.7)12P X a ==,1()3P X a ==,1( 1.1)4P X a ==,1( 1.3)12P X a ==.所以X 的分布列为:0.90.80.7 1.1 1.39426121234121212EX a a a a a a =⨯+⨯+⨯+⨯+⨯+⨯==≈.(2)①由统计数据可知任意一辆该品牌车龄已满三年的二手车为事故的概率为13,三辆车中至多有一辆事故车的概率为:321311220133327P C ⎛⎫⎛⎫=-+= ⎪ ⎪⎝⎭⎝⎭. ②设Y 为给销售商购进并销售一辆二手车的利润,Y 的可能取值为5000,10000- 所以Y 的分布列为:所以500010000500033EY =-⨯+⨯=. 所以该销售商一次购进100辆该品牌车龄已满三年的二手车获得利润的期望值为10050EY ⨯=万元.点评:本题考查离散型随机变量及分布列,考查二项分布,考查计算能力,是基础题 21.已知函数1()ln ,a f x x x -=+()sin 12(),a x g x a R x+-=∈. (1)求函数()f x 的极小值;(2)求证:当11a -≤≤时,()()f x g x >. 答案:(1)见解析(2)见解析 (1)由题意可得()()21,0x a f x x x'--=>()分类讨论函数的极小值即可. (2)令()()()()1211,(0)a sinx a xlnx asinx F x f x g x lnx x x x x+---+=-=+-=>,原问题等价于()0F x >,即证1xlnx asinx >-.据此分类讨论01a <≤,=0a 和10a -≤<三种情况即可证得题中的结论. 解: (1)()()22111,0x a a f x x x x x()---=-=>' 当10a -≤时,即1a ≤时,()0f x '>,函数()f x 在()0,+∞上单调递增,无极小值;当10a ->时,即1a >时,()0,01f x x a <⇒<<-',函数()f x 在()0,1a -上单调递减;()0,1f x x a >⇒>-',函数()f x 在()1,a -+∞上单调递增; ()()()=111f x f a ln a -=+-极小,综上所述,当1a ≤时,()f x 无极小值;当1a >时,()()11f x ln a =+-极小 (2)令()()()()1211,(0)a sinx a xlnx asinx F x f x g x lnx x x x x+---+=-=+-=> 当11a -≤≤时,要证:()()f x g x >,即证()0F x >,即证10xlnx asinx -+>, 要证10xlnx asinx -+>,即证1xlnx asinx >-. ①当01a <≤时,令()h x x sinx =-,()10h x cosx -'=≥,所以()h x 在()0,+∞单调递增, 故()()00h x h >=,即x sinx >. 11*ax asinx ∴->-(), 令()1q x xlnx x =-+,()=q x lnx ',当()()0,1,0x q x ∈'<,()q x 在()0,1单调递减;()()1,,0x q x '∈+∞>,()q x 在()1,+∞单调递增,故()()10q x q ≥=,即1xlnx x ≥-.当且仅当1x =时取等号又01a <≤,11**xlnx x ax ∴≥-≥-() 由*()、**()可知111xlnx x ax asinx ≥-≥->- 所以当01a <≤时,1xlnx asinx >-②当=0a 时,即证1xlnx >-.令()=m x xlnx ,()=1m x lnx +',()m x 在10,e ⎛⎫ ⎪⎝⎭上单调递减,在1,e ⎛⎫+∞ ⎪⎝⎭上单调递增,()11=1min m x m e e⎛⎫=->- ⎪⎝⎭,故1xlnx >- ③当10a -≤<时,当0,1]x ∈(时,11asinx -<-,由②知()1m x xlnx e=≥-,而11e->-, 故1xlnx asinx >-;当1,x ∈+∞()时,10asinx -≤,由②知()()10m x xlnx m =>=,故1xlnx asinx >-;所以,当0,x ∈+∞()时,1xlnx asinx >-.综上①②③可知,当11a -≤≤时,()()f x g x >. 点评:导数是研究函数的单调性、极值(最值)最有效的工具,而函数是高中数学中重要的知识点,对导数的应用的考查主要从以下几个角度进行:(1)考查导数的几何意义,往往与解析几何、微积分相联系.(2)利用导数求函数的单调区间,判断单调性;已知单调性,求参数.(3)利用导数求函数的最值(极值),解决生活中的优化问题.(4)考查数形结合思想的应用.22.选修4-4:坐标系与参数方程在平面直角坐标系xOy 中,直线l的参数方程为121x t y ⎧=⎪⎪⎨⎪=⎪⎩(t 为参数),在以坐标原点为极点,x 轴的正半轴为极轴的极坐标系中,曲线C 的极坐标方程为sin a ρθ=(a R ∈且0a ≠).(I )求直线l 的极坐标方程及曲线C 的直角坐标方程; (Ⅱ)已知()1,A ρθ是直线l 上的一点,2,6B πρθ⎛⎫+⎪⎝⎭是曲线C 上的一点,1R ρ∈,2R ρ∈,若||||OB OA 的最大值为2,求a 的值. 答案:(I)1sin 32πρθ⎛⎫-= ⎪⎝⎭;220x y ay +-=.(Ⅱ)2a =± (I )利用参数方程、极坐标方程和普通方程互化的公式求直线l 的极坐标方程及曲线C 的直角坐标方程;(Ⅱ)先利用极坐标方程求出11sin 32πρθ⎛⎫-= ⎪⎝⎭,2sin 6a πρθ⎛⎫=+ ⎪⎝⎭,再求出21||||OB OA ρρ==sin 23a πθ⎛⎫+ ⎪⎝⎭,即得sin 2||=23a a πθ⎛⎫+≤ ⎪⎝⎭,解之即得a 的值. 解:解:(I )消去参数t ,得直线l10y -+=, 由cos x ρθ=,sin y ρθ=,得直线l的极坐标方程为sin )10ρθθ-+=,即1sin 32πρθ⎛⎫-= ⎪⎝⎭. 曲线C 的极坐标方程为sin a ρθ=(a R ∈且0a ≠),即sin a ρθ=,由222x y ρ=+,sin y ρθ=,得曲线C 的直角坐标方程为220x y ay +-=.(Ⅱ)∵()1,A ρθ在直线l 上,2,6B πρθ⎛⎫+ ⎪⎝⎭在曲线C 上, ∴11sin 32πρθ⎛⎫-= ⎪⎝⎭,2sin 6a πρθ⎛⎫=+ ⎪⎝⎭, ∴21||2sin sin ||63OB a OA ρππθθρ⎛⎫⎛⎫==+- ⎪ ⎪⎝⎭⎝⎭ 2sin cos sin 2||663a a a πππθθθ⎛⎫⎛⎫⎛⎫=++=+≤ ⎪ ⎪ ⎪⎝⎭⎝⎭⎝⎭ ∴||2a =,2a =±.点评:本题主要考查参数方程、极坐标方程和普通方程的互化,考查三角恒等变换和三角函数的图像和性质,意在考查学生对这些知识的理解掌握水平和分析推理能力.23.设函数()13f x x x =--+.(1)求不等式()1f x ≤的解集;(2)若函数()f x 的最大值为m ,正实数,p q 满足2p q m +=,求212p q++的最小值. 答案:(1)32x x ⎧⎫≥-⎨⎬⎩⎭(2)见解析 (1)不等式可化为3131x x x ≤-⎧⎨-++≤⎩或31111x x x -<<⎧⎨---≤⎩或1131x x x ≥⎧⎨---≤⎩,据此求解不等式的解集即可;(2)由题意可得4m =,结合均值不等式的求解212p q++的最小值即可,注意等号成立的条件.解:(1)不等式可化为3131x x x ≤-⎧⎨-++≤⎩或31111x x x -<<⎧⎨---≤⎩或1131x x x ≥⎧⎨---≤⎩解得32x ≥- ()1f x ∴≤的解集为32x x ⎧⎫≥-⎨⎬⎩⎭ (2)13134x x x x ---≤-++=,()4,24226m p q p q ∴=+=∴++=,()2112114222426262q p p q p q p q p q ⎛⎫⎛⎫++=+++=++ ⎪ ⎪+++⎝⎭⎝⎭14463⎛≥+= ⎝. 当且仅当223p q +==时,即132p q =⎧⎪⎨=⎪⎩时,取“=”, 212p q ∴++的最小值为43. 点评:绝对值不等式的解法:法一:利用绝对值不等式的几何意义求解,体现了数形结合的思想; 法二:利用“零点分段法”求解,体现了分类讨论的思想;法三:通过构造函数,利用函数的图象求解,体现了函数与方程的思想.。

2020年高考英语全国Ⅲ卷(解析版)

2020年高考英语全国Ⅲ卷(解析版)
21.What can visitors see in both Classical Provence and Southern Spain?
A.Historical monuments.B.Fields of flowers.
C.Van Gogh’s paintings.D.Greek buildings.
【23题详解】
细节理解题。根据第四部分的Tour highlights include the Roman city of Dougga, the underground Mumidian capital at Bulla Regia, Roman Sbeitla and the remote areas around Taraounine and Matmata, unique for underground cities.(突尼斯的旅游亮点包括罗马城市Dougga,地下城市Mumidian,它是Bulla Regia的首府,Roman Sbeitla以及在Taraounine和Matmata附近的区域,它们是独特的地下城市)可知,突尼斯的旅游亮点是地下城市。A. Underground cities(地下城市)符合以上说法,故选A项。
【22题详解】
推理判断题。根据第三部分的China's Sacred Landscapes (21days)(中华神山21天)和Discover the China of ''past ages'', its walled cities, temples and mountain scenery with Prof Robert Thorp. Highlights include China's most sacred peaks at Mount Tai and Hangzhou's rolling hills, waterways and peaceful temples (和Robert教授一起发现中国的过去,有墙的城市、寺庙和山景。精彩之处包括中国最神圣的泰山之巅,杭州起伏的群山、运河和宁静的寺庙)可知,去中国的神山之行总共有27天,而且Thorp对中国的名山非常了解。由此推测Thorp在这四个国家里最了解中国。C. China(中国)符合以上说法,故选C项。

2020年高考英语试卷(全国新高考Ⅰ卷)【word版本;可编辑;含答案】

2020年高考英语试卷(全国新高考Ⅰ卷)【word版本;可编辑;含答案】

2020年高考英语试卷(全国新高考Ⅰ卷)一、阅读理解1.POETRY CHALLENGEWrite a poem about how courage, determination, and strength have helped you face challenges in your life.Prizes3 Grand Prizes: Trip to Washington, D.C. for each of three winners, a parent and one other person of the winner's choice. Trip includes round-trip air tickets, hotel stay for two nights, and tours of the National Air and Space Museum and the office of National Geographic World.6 First Prizes: The book Sky Pioneer: A Photobiography of Amelia Earhart signed by author Corinne Szabo and pilot Linda Finch.50 Honorable Mentions: Judges will choose up to 50 honorable mention winners, who will each receive a T-shirt in memory of Earhart's final flight. RulesFollow all rules carefully to prevent disqualification.■ Write a poem using 100 words or fewer. Your poem can be any format, any number of lines. ■ Write by hand or type on a single sheet of paper. You may use both the front and back of the paper.■ On the same sheet of paper, write or type your name, address, telephone number, and birth date.■ Mail your entry to us by October 31 this year.(1)How many people can each grand prize winner take on the free trip? A.Two. B.Three. C.Four. D.Six.(2)What will each of the honorable mention winners get?A.A plane ticket.B.A book by Corinne Szabo.C.A special T-shirt.D.A photo of Amelia Earhart.(3)Which of the following will result in disqualification?A.Typing your poem out.B.Writing a poem of 120 words.ing both sides of the paper.D.Mailing your entry on October 30.2.Jennifer Mauer has needed more willpower than the typical college studentto pursue her goal of earning a nursing degree. That willpower bore fruit when Jennifer graduated from University of Wisconsin-Eau Claire and became the first in her large family to earn a bachelor's degree.Mauer, of Edgar, Wisconsin, grew up on a farm in a family of 10 children. Her dad worked at a job away from the farm, and her mother ran the farm with the kids. After high school, Jennifer attended a local technical college, working to pay her tuition (学费), because there was no extra money set aside for a college education. After graduation, she worked to help her sisters and brothers pay for their schooling.Jennifer now is married and has three children of her own. She decided to go back to college to advance her career and to be able to better support her family while doing something she loves: nursing. She chose the UW-Eau Claire program at Ministry Saint Joseph Hospital in Marshfield because she was able to pursue her four-year degree close to home. She could drive to class and be home in the evening to help with her kids. Jennifer received great support from her family as she worked to earn her degree: Her husband worked two jobs to cover the bills, and her 68-year-old mother helped take care of the children at times.Through it all, she remained in good academic standing and graduated with honors. Jennifer sacrificed (牺牲)to achieve her goal, giving up many nights with her kids and missing important events to study. "Some nights my heart was breaking to have to pick between my kids and studying for exams or papers," she says. However, her children have learned an important lesson witnessing their mother earn her degree. Jennifer is a first-generation graduate and an inspiration to her family—and that's pretty powerful.(1)What did Jennifer do after high school?A.She helped her dad with his work.B.She ran the family farm on her own.C.She supported herself through college.D.She taught her sisters and brothers at home.(2)Why did Jennifer choose the program at Ministry Saint Joseph's Hospital in Marshfield?A.To take care of her kids easily.B.To learn from the best nurses.C.To save money for her parents.D.To find a well-paid job there.(3)What did Jennifer sacrifice to achieve her goal?A.Her health.B.Her time with family.C.Her reputation.D.Her chance of promotion.(4)What can we learn from Jennifer's story?A.Time is money.B.Love breaks down barriers.C.Hard work pays off.cation is the key to success.3.In the mid-1990s, Tom Bissell taught English as a volunteer in Uzbekistan. He left after seven months, physically broken and having lost his mind. A few years later, still attracted to the country, he returned to Uzbekistan to write an article about the disappearance of the Aral Sea.His visit, however, ended up involving a lot more than that. Hence this book, Chasing the Sea: Lost Among the Ghosts of Empire in Central Asia, which talks about a road trip from Tashkent to Karakalpakstan, where millions of lives have been destroyed by the slow drying up of the sea. It is the story of an American travelling to a strange land, and of the people he meets on his way: Rustam, his translator, a lovely 24-year-old who picked up his colorful English in California, Oleg and Natasha, his hosts in Tashkent, and a string of foreign aid workers.This is a quick look at life in Uzbekistan, made of friendliness and warmth, but also its darker side of society. In Samarkand, Mr Bissell admires the architectural wonders, while on his way to Bukhara he gets a taste of police methods when suspected of drug dealing. In Ferghana, he attends a mountain funeral (葬礼)followed by a strange drinking party. And in Karakalpakstan, he is saddened by the dust storms, diseases and fishing boats stuck miles from the sea.Mr Bissell skillfully organizes historical insights and cultural references, making his tale a well-rounded picture of Uzbekistan, seen from Western eyes. His judgment and references are decidedly American, as well as his delicate stomach. As the author explains, this is neither a travel nor a history book, or even a piece of reportage. Whatever it is, the result is a fine and vivid description of the purest of Central Asian traditions.(1)What made Mr Bissell return to Uzbekistan?A.His friends' invitation.B.His interest in the country.C.His love for teaching.D.His desire to regain health.。

2025届高三10月大联考试题(新高考卷)英语 PDF版含解析

2025届高三10月大联考试题(新高考卷)英语 PDF版含解析

2025届高三10月大联考(新课标卷)英语·全解全析及评分标准第一部分听力(共两节,满分30分)1—5 BCCAC 6—10 AABCB 11—15 ACACB 16—20 CABAB第二部分阅读(共两节,满分50分)第一节(共15小题;每小题2.5分,满分37.5分)A【语篇解读】这是一篇应用文,介绍了四款跑步手表。

21. B 【解析】细节理解题。

对比四款手表的介绍可知,第一款手表Garmin Forerunner 245的价格只有120英镑,其他手表的价格都比它高,即这款手表便宜。

故选B。

22. C 【解析】细节理解题。

根据第三款手表Honor Watch GS Pro下面的“Look out in particular for the routeback function and route deviation (偏离) warning, which help users explore their potential without worries”可知,这款手表有路线返回功能和路线偏离警报功能,适合方向感差的人,故选C。

23. A 【解析】细节理解题。

根据Coros Vertix下的“the Vertix claimed to have a longer battery life than any otherwatch”和Suunto 7下的“Battery life will support a full day of active smartwatch use and still have enough juice left for your daily workout”可知,这两款手表都具有续航持久的特点,故选A。

B【语篇解读】这是一篇记叙文。

North County的一个试点项目正在教授学生关于营养和食物来源的知识,该项目鼓励小学生尝试他们以前可能没有尝试过的蔬菜。

24. D 【解析】推理判断题。

2020届全国100所名校最新高考模拟示范卷(四)高三数学(理)试题及答案

2020届全国100所名校最新高考模拟示范卷(四)高三数学(理)试题及答案

绝密★启用前2020届全国100所名校最新高考模拟示范卷(四)高三数学(理)试题注意事项:1、答题前填写好自己的姓名、班级、考号等信息2、请将答案正确填写在答题卡上 一、单选题 1.已知集合{}|26Mx x =-<<,{}2|3log 35N x x =-<<,则MN =( )A .{}2|2log 35x x -<<B .{}2|3log 35x x -<<C .{}|36x x -<<D .{}2|log 356x x <<答案:A根据对数性质可知25log 356<<,再根据集合的交集运算即可求解. 解:∵25log 356<<, 集合{}|26Mx x =-<<,∴由交集运算可得{}2|2log 35M N x x ⋂=-<<.故选:A. 点评:本题考查由对数的性质比较大小,集合交集的简单运算,属于基础题. 2.设复数z 满足12z zz +=+,z 在复平面内对应的点的坐标为(),x y 则( ) A .221x y =+ B .221y x =+ C .221x y =- D .221y x =-答案:B根据共轭复数定义及复数模的求法,代入化简即可求解. 解:z 在复平面内对应的点的坐标为(),x y ,则z x yi =+,z x yi =-,∵12z zz +=+,1x =+,解得221y x =+. 故选:B. 点评:本题考查复数对应点坐标的几何意义,复数模的求法及共轭复数的概念,属于基础题. 3.“2b =”是“函数()()2231f x b b x α=--(α为常数)为幂函数”的( )A .充分不必要条件B .必要不充分条件C .充要条件D .既不充分又不必要条件答案:A根据幂函数定义,求得b 的值,结合充分条件与必要条件的概念即可判断. 解:∵当函数()()2231af x b b x =--为幂函数时,22311b b --=,解得2b =或12-, ∴“2b =”是“函数()()2231af x b b x =--为幂函数”的充分不必要条件.故选:A. 点评:本题考查了充分必要条件的概念和判断,幂函数定义的应用,属于基础题.4.已知()21AB =-,,()1,AC λ=,若cos BAC ∠=,则实数λ的值是( ) A .-1 B .7C .1D .1或7答案:C根据平面向量数量积的坐标运算,化简即可求得λ的值. 解:由平面向量数量积的坐标运算,代入化简可得cos 105AB AC BAC AB AC⋅∠===. ∴解得1λ=. 故选:C. 点评:本题考查了平面向量数量积的坐标运算,属于基础题.5.嫦娥四号月球探测器于2018年12月8日搭载长征三号乙运载火箭在西昌卫星发射中心发射.12日下午4点43分左右,嫦娥四号顺利进入了以月球球心为一个焦点的椭圆形轨道,如图中③所示,其近月点与月球表面距离为100公里,远月点与月球表面距离为400公里,已知月球的直径约为3476公里,对该椭圆有下述四个结论: (1)焦距长约为300公里; (2)长轴长约为3988公里; (3)两焦点坐标约为()150,0±; (4)离心率约为75994. 其中正确结论的个数为()A .1B .2C .3D .4答案:B根据椭圆形轨道,设该椭圆长轴长为a ,半焦距为c ,先求得月球的半径r ,再根据近月点与月球表面距离为100公里,有100a c r -=+,远月点与月球表面距离为400公里,有400a c r +=+,然后两式联立求解. 解:设该椭圆长轴长为a ,半焦距为c ,依题意可得月球半径约为1347617382⨯=, 所以1001738183840017382138a c a c -=+=⎧⎨+=+=⎩,解得1988150a c =⎧⎨=⎩所以离心率150751988994c e a ===,可知结论(1)(4)正确,(2)错误; 因为没有给坐标系,焦点坐标不确定,所以(3)错误. 故选:B 点评:本题主要考查椭圆的几何性质,还考查了阅读抽象应用的能力,属于基础题. 6.在ABC 中,内角A ,B ,C 所对的边分别为a ,b ,c ,若1a =,6A π=,且321c b -=,则cos C ()A .12-B .3C .12D 6 答案:A根据1a =,321c b -=,由正弦定理边化为角得到3sin 2sin sin C B A -=,由A B C π++=,得到()3sin 2sin sin C A C A -+=,再根据6A π=求解.解:由321c b -=,得32c b a -=,即3sin 2sin sin C B A -=, 所以()3sin 2sin sin C A C A -+=, 而6A π=,所以3sin 2sin sin 66C C ππ⎛⎫-+= ⎪⎝⎭, 即3113sin 2sin cos 222C C C ⎛⎫-+= ⎪ ⎪⎝⎭, 解得1cos 2C =-. 故选:A 点评:本题主要考查正弦定理和三角恒等变换,还考查了运算求解的能力,属于中档题. 7.函数()2cos2cos221xxf x x =+-的图象大致是( ) A . B .C .D .答案:C根据函数奇偶性可排除AB 选项;结合特殊值,即可排除D 选项. 解:∵()2cos221cos2cos22121x x x x f x x x +=+=⨯--,()()()2121cos 2cos22121x x x x f x x x f x --++-=⨯-=-⨯=---,∴函数()f x 为奇函数,∴排除选项A ,B ;又∵当04x π⎛⎫∈ ⎪⎝⎭,时,()0f x >,故选:C. 点评:本题考查了依据函数解析式选择函数图象,注意奇偶性及特殊值的用法,属于基础题.8.设x ,y 满足约束条件2010x y x y x m -+≥⎧⎪+-≥⎨⎪≤⎩,若2z x y =+的最大值大于17,则实数m 的取值范围为() A .()4,+∞ B .13,2⎛⎫+∞⎪⎝⎭C .()6,+∞D .()5,+∞答案:D先作出不等式组表示的平面区域,然后平移直线l :20x y +=,当直线l 在y 轴上的截距最大时,z 取得最大值求解. 解:作出不等式组表示的平面区域如图所示,作出直线l :20x y +=,并平移,当直线l 经过点(),2m m +时,直线在y 轴上的截距最大,z 取得最大值, 因为2z x y =+的最大值大于17, 所以2217m m ++>,解得5m >. 故选:D 点评:本题主要考查线性规划求最值,还考查了数形结合的方法的能力,属于基础题. 9.七巧板是一种古老的中国传统智力玩具,是由七块板组成.而这七块板可拼成许多图形,人物、动物、建筑物等,在18世纪,七巧板流传到了国外,至今英国剑桥大学的图书馆里还珍藏着一部《七巧图谱》.若用七巧板(图1为正方形),拼成一只雄鸡(图2),在雄鸡平面图形上随机取一点,则恰好取自雄鸡鸡头或鸡尾(阴影部分)的概率为A .112B .18C .14D .316答案:D这是一个几何概型模型,设包含7块板的正方形边长为4,求得正方形的面积,即为雄鸡的面积,然后求得雄鸡鸡头(标号3或5)和鸡尾(标号6)的面积之和,代入公式求解. 解:设包含7块板的正方形边长为4,正方形的面积为4416⨯=, 则雄鸡鸡头(标号3或5)和鸡尾(标号6)的面积之和为1212132⨯⨯+⨯=, 在雄鸡平面图形上随机取一点,则恰好取自雄鸡几头或鸡尾(阴影部分)的概率为316p. 故选:D 点评:本题主要考查几何概型的概率,还考查了阅读抽象应用的能力,属于基础题.10.如图,直三棱柱ABC A B C '''-的侧棱长为3,AB BC ⊥,3AB BC ==,点E ,F 分别是棱AB ,BC 上的动点,且AE BF =,当三棱锥B EBF '-的体积取得最大值时,则异面直线A F '与AC 所成的角为()A .2π B .3π C .4π D .6π 答案:C设AE BF a ==,13B EBF EBFV S B B '-'=⨯⨯,利用基本不等式,确定点E ,F 的位置,然后根据//EF AC ,得到A FE '∠即为异面直线A F '与AC 所成的角,再利用余弦定理求解.设AE BF a ==,则()()23119333288B EBFaa V a a '-+-⎡⎤=⨯⨯⨯-⨯≤=⎢⎥⎣⎦,当且仅当3a a =-,即32a =时等号成立, 即当三棱锥B EBF '-的体积取得最大值时,点E ,F 分别是棱AB ,BC 的中点, 方法一:连接A E ',AF ,则352A E '=,352AF =,2292A F AA AF ''=+=,13222EF AC ==, 因为//EF AC ,所以A FE '∠即为异面直线A F '与AC 所成的角,由余弦定理得222819452424cos 9322222A F EF A E A FE A F EF +-''+-'∠==='⋅⋅⨯⨯, ∴4A FE π'∠=.方法二:以B 为坐标原点,以BC 、BA 、BB '分别为x 轴、y 轴、z 轴建立空间直角坐标系,则()0,3,0A ,()3,0,0C ,()0,3,3A ',3,0,02F ⎛⎫⎪⎝⎭, ∴3,3,32A F ⎛⎫'=--⎪⎝⎭,()3,3,0AC =-, 所以9922cos ,92322A F AC A F AC A F AC +'⋅'==='⋅⨯,所以异面直线A F '与AC 所成的角为4π. 故选:C 点评:本题主要考查异面直线所成的角,余弦定理,基本不等式以及向量法求角,还考查了推理论证运算求解的能力,属于中档题.11.已知函数()sin f x a x x =的一条对称轴为56x π=,函数()f x 在区间()12,x x 上具有单调性,且()()12f x f x =-,则下述四个结论:①实数a 的值为1;②()()1,x f x 和()()22,x f x 两点关于函数()f x 图象的一条对称轴对称; ③21x x -的最大值为π, ④12x x +的最小值为23π. 其中所有正确结论的编号是() A .①②③ B .①③④C .①④D .③④答案:B 根据56x π=是函数()f x 的一条对称轴,确定函数()f x ,再根据函数()f x 在区间()12,x x 上具有单调性,得到21x x -的最大值为2Tπ=,然后由()()12f x f x =-,得到()()11,x f x 和()()22,x f x 两点关于函数()f x 的一个对称中心对称求解验证. 解: ∵56x π=是函数()f x 的一条对称轴,∴()53f x f x π⎛⎫=-⎪⎝⎭, 令0x =,得()503f f π⎛⎫=⎪⎝⎭,即=1a =,①正确; ∴()sin 2sin 3π⎛⎫==- ⎪⎝⎭f x x x x .又因为函数()f x 在区间()12,x x 上具有单调性, ∴21x x -的最大值为2Tπ=,且()()12f x f x =-, ∴()()11,x f x 和()()22,x f x 两点关于函数()f x 的一个对称中心对称,∴121233223x x x x k ππ⎛⎫⎛⎫-+- ⎪ ⎪+π⎝⎭⎝⎭=-=π,k Z ∈, ∴12223x x k ππ+=+,k Z ∈, 当0k =时,12x x +取最小值23π,所以①③④正确,②错误.故选:B 点评:本题主要考查三角函数的图象和性质,还考查了推理论证,运算求解的能力,属于中档题.12.如图,在ABC 中,AB 4=,点E 为AB 的中点,点D 为线段AB 垂直平分线上的一点,且4DE =,固定边AB ,在平面ABD 内移动顶点C ,使得ABC 的内切圆始终与AB 切于线段BE 的中点,且C 、D 在直线AB 的同侧,在移动过程中,当CA CD +取得最小值时,ABC 的面积为()A .12524-B .6512-C .12518-D .658-答案:A以AB 所在直线为x 轴,ED 所在直线为y 轴建立平面直角坐标系,利用圆的切线长定理,得到C 点的轨迹是以A 、B 为焦点的双曲线在第一象限部分,然后利用直线段最短,得到点C 的位置,再求三角形的面积. 解: 如图,以AB 所在直线为x 轴,ED 所在直线为y 轴建立平面直角坐标系,则()2,0A -,()2,0B ,()0,4D ,设ABC 的内切圆分别切BC 、AC 、AB 于F ,G ,H 点,∵3124CA CB AG BF AH HB -=-=-=-=<,所以C 点的轨迹是以A 、B 为焦点的双曲线的第一象限部分,且1a =,2c =,2223b c a =-=,∴C 的轨迹方程为()220,03y x x y ->>.∵2CA CB -=,∴2CA CB =+,∴2CA CD CB CD +=++, 则当点C 为线段BD 与双曲线在第一象限的交点时,CA CD +最小, 如图所示:线段BD 的方程为()4202y x x =-≤≤,将其代入22330x y --=,得216190x x -+=,解得835x =+835x =-,∴426512y x =-=, ∴()835,6512C -. ∴ABC 的面积为()146512125242⨯⨯=. 故选:A 点评:本题主要考查双曲线的定义,圆的切线长定理以及三角形的面积,还考查了数形结合的思想和运算求解的能力,属于中档题. 二、填空题13.若函数()()()()()2log 2242x x f x f x x ⎧->⎪=⎨+≤⎪⎩,则()()5f f -=__________. 答案:1利用分段函数,先求()5f -,再求()()5f f -的值.解: ∵()()()5130f f f -=-==,∴()()()()5041ff f f -===.故答案为:1 点评:本题主要考查分段函数求函数值问题,还考查了运算求解的能力,属于基础题. 14.若()()613x a x -+的展开式中3x 的系数为45-,则实数a =__________. 答案:13利用通项公式得到()()613x a x -+的展开式中含3x 的项为:()()23236633x C x a C x ⋅-⋅,再根据系数为45-,建立方程求解.解:因为()()613x a x -+的展开式中含3x 的项为:()()()232336633135540x C x a C x a x ⋅-⋅=-,∴13554045a -=-,解得13a =. 故答案为:13点评:本题主要考查二项式定理的通项公式,还考查了运算求解的能力,属于基础题. 15.如图,在矩形ABCD 中,24==AD AB ,E 是AD 的中点,将ABE △,CDE △分别沿BE CE ,折起,使得平面ABE ⊥平面BCE ,平面CDE ⊥平面BCE ,则所得几何体ABCDE 的外接球的体积为__________.答案:323π 根据题意,画出空间几何体,设BE EC BC ,,的中点分别为M N O ,,,并连接AM CM AO DN NO DO OE ,,,,,,,利用面面垂直的性质及所给线段关系,可知几何体ABCDE 的外接球的球心为O ,即可求得其外接球的体积. 解:由题可得ABE △,CDE △,BEC △均为等腰直角三角形,如图所示,设BE EC BC ,,的中点分别为M N O ,,, 连接AM CM AO DN NO DO OE ,,,,,,, 则OM BE ⊥,ON CE ⊥.因为平面ABE ⊥平面BCE ,平面CDE ⊥平面BCE , 所以OM ⊥平面ABE ,ON ⊥平面DEC , 易得2OA OB OC OD OE =====,则几何体ABCDE 的外接球的球心为O ,半径2R =, 所以几何体ABCDE 的外接球的体积为343233V R ππ==. 故答案为:323π. 点评:本题考查了空间几何体的综合应用,折叠后空间几何体的线面位置关系应用,空间几何体外接球的性质及体积求法,属于中档题.16.若函数()2ln 2f x x x ax x =--有两个不同的极值点,则实数a 的取值范围为__________. 答案:10,4e ⎛⎫ ⎪⎝⎭由函数()2ln 2f x x x ax x =--有两个不同的极值点,则()ln 40f x x ax '=-=有两个不同的根,转化为方程ln 4x a x =有两个不同解,即函数()g x ln 4xx=的图象与直线y a =有两个公共点求解.解:由()ln 40f x x ax '=-=,得ln 4xa x=, 记()ln 4x g x x =,则()21ln 4xg x x-'=, 当()0,x e ∈时,()0g x '>,()g x 单调递增,当(),x e ∈+∞时,()0g x '<,()g x 单调递减. 又∵()14g e e=,当0x →时,()g x →-∞,当x →+∞时,()0g x →. 因为函数()2ln 2f x x x ax x =--有两个不同的极值点, 所以方程ln 4xa x=有两个不同的解, 即函数()g x 的图象与直线y a =有两个公共点, 故实数a 的取值范围为10,4e ⎛⎫ ⎪⎝⎭. 故答案为:10,4e ⎛⎫ ⎪⎝⎭点评:本题主要考查导数与函数的极值点以及导数与函数的零点问题,还考查了数形结合的思想和运算求解的能力,属于中档题. 三、解答题17.在如图所示的多面体中,四边形ABEG 是矩形,梯形DGEF 为直角梯形,平面DGEF ⊥平面ABEG ,且DG GE ⊥,//DF GE ,2222AB AG DG DF ====.(1)求证:FG ⊥平面BEF . (2)求二面角A BF E --的大小. 答案:(1)见解析;(2)23π(1)根据面面垂直性质及线面垂直性质,可证明BE FG ⊥;由所给线段关系,结合勾股定理逆定理,可证明FE FG ⊥,进而由线面垂直的判定定理证明FG ⊥平面BEF .(2)建立空间直角坐标系,写出各个点的坐标,并求得平面AFB 和平面EFB 的法向量,由空间向量法求得两个平面夹角的余弦值,结合图形即可求得二面角A BF E --的大小. 解:(1)证明:∵平面DGEF ⊥平面ABEG ,且BE GE ⊥, ∴BE ⊥平面DGEF , ∴BE FG ⊥,由题意可得2FG FE ==, ∴222FG FE GE +=,∵FE FG ⊥,且FE BE E ⋂=, ∴FG ⊥平面BEF .(2)如图所示,建立空间直角坐标系,则()1,0,0A ,()1,2,0B ,()0,2,0E ,()0,1,1F ,()1,1,1FA =--,()1,1,1FB =-,()0,1,1FE =-.设平面AFB 的法向量是()111,,n x y z =,则11111111100000x y z x z FA n x y z y FB n --==⎧⎧⎧⋅=⇒⇒⎨⎨⎨+-==⋅=⎩⎩⎩,令11x =,()1,0,1n =,由(1)可知平面EFB 的法向量是()0,1,1m GF ==,∴1cos<,222n m n m n m⋅>===⨯⋅,由图可知,二面角A BF E --为钝二面角,所以二面角A BF E --的大小为23π. 点评:本题考查了线面垂直的判定,面面垂直及线面垂直的性质应用,空间向量法求二面角的大小,属于中档题.18.在等差数列{}n a 中,12a =,35730a a a ++=.(1)求数列{}n a 的通项公式;(2)记23n n a an b =+,当*n N ∈时,1n n b b λ+>,求实数λ的取值范围.答案:(1)2n a n =(2)实数λ的取值范围是97,13⎛⎫-∞ ⎪⎝⎭(1)根据12a =,35730a a a ++=,利用“1,a d ”法求解.(2)由(1)得到2349n naa n n nb =+=+,将()114949n n n n λ+++>+对*n N ∀∈恒成立,转化为5419nλ<⎛⎫+ ⎪⎝⎭对*n N ∀∈恒成立求解. 解:(1)在等差数列{}n a 中,3575330a a a a ++==,∴510a =,所以{}n a 的公差51251a a d -==-, ∴()112n a a n d n =+-=. (2)∵2349n naa n n nb =+=+,∴()114949n n n n λ+++>+对*n N ∀∈恒成立,即4499595444949419n n n n n n n n λ⨯+⨯⨯<=+=+++⎛⎫+ ⎪⎝⎭对*n N ∀∈恒成立, 又∵55974441341199n+≥+=⎛⎫++ ⎪⎝⎭,∴9713λ<,即实数λ的取值范围是97,13⎛⎫-∞ ⎪⎝⎭.点评:本题主要考查等差数列的基本运算以及有关数列的不等式恒成立问题,还考查了运算求解的能力,属于中档题.19.在直角坐标系xOy 中,曲线1C 上的任意一点M 到直线1y =-的距离比M 点到点()02F ,的距离小1.(1)求动点M 的轨迹1C 的方程;(2)若点P 是圆()()222221C x y -++=:上一动点,过点P 作曲线1C 的两条切线,切点分别为A B 、,求直线AB 斜率的取值范围.答案:(1)28x y =;(2)13,44⎡⎤⎢⎥⎣⎦(1)设(),M x y ,根据题意可得点M 的轨迹方程满足的等式,化简即可求得动点M 的轨迹1C 的方程;(2)设出切线PA PB 、的斜率分别为12k k ,,切点()12,A x x ,()22,B x y ,点()P m n ,,则可得过点P 的拋物线的切线方程为()y k x m n =-+,联立抛物线方程并化简,由相切时0∆=可得两条切线斜率关系12,k k +12k k ;由抛物线方程求得导函数,并由导数的几何意义并代入抛物线方程表示出12,y y ,可求得4AB mk =,结合点()P m n ,满足()()22221x y -++=的方程可得m 的取值范围,即可求得AB k 的范围.解:(1)设点(),M x y ,∵点M 到直线1y =-的距离等于1y +, ∴11y +=,化简得28x y =,∴动点M 的轨迹1C 的方程为28x y =.(2)由题意可知,PA PB 、的斜率都存在,分别设为12k k ,,切点()12,A x x ,()22,B x y ,设点()P m n ,,过点P 的拋物线的切线方程为()y k x m n =-+,联立()28y k x m n x y⎧=-+⎨=⎩,化简可得28880x kx km n -+-=,∴26432320k km n ∆=-+=,即220k km n -+=, ∴122m k k +=,122n k k =. 由28x y =,求得导函数4xy '=, ∴114x k =,2211128x y k ==,2222228x y k ==,∴222121212121224424ABy y k k k k m k x x k k --+====--, 因为点()P m n ,满足()()22221x y -++=, 由圆的性质可得13m ≤≤,∴13444AB m k ≤=≤,即直线AB 斜率的取值范围为13,44⎡⎤⎢⎥⎣⎦. 点评:本题考查了动点轨迹方程的求法,直线与抛物线相切的性质及应用,导函数的几何意义及应用,点和圆位置关系求参数的取值范围,属于中档题.20.某大学开学期间,该大学附近一家快餐店招聘外卖骑手,该快餐店提供了两种日工资结算方案:方案()a 规定每日底薪100元,外卖业务每完成一单提成2元;方案()b 规定每日底薪150元,外卖业务的前54单没有提成,从第55单开始,每完成一单提成5元.该快餐店记录了每天骑手的人均业务量,现随机抽取100天的数据,将样本数据分为[)[)[)[)[)[)[]2535354545555565657575858595,,,,,,,,,,,,,七组,整理得到如图所示的频率分布直方图.(1)随机选取一天,估计这一天该快餐店的骑手的人均日外卖业务量不少于65单的概率;(2)从以往统计数据看,新聘骑手选择日工资方案()a 的概率为13,选择方案()b 的概率为23.若甲、乙、丙、丁四名骑手分别到该快餐店应聘,四人选择日工资方案相互独立,求至少有两名骑手选择方案()a 的概率,(3)若仅从人日均收入的角度考虑,请你为新聘骑手做出日工资方案的选择,并说明理由.(同组中的每个数据用该组区间的中点值代替) 答案:(1)0.4;(2)1127;(3)应选择方案()a ,理由见解析 (1)根据频率分布直方图,可求得该快餐店的骑手的人均日外卖业务量不少于65单的频率,即可估算其概率;(2)根据独立重复试验概率求法,先求得四人中有0人、1人选择方案()a 的概率,再由对立事件概率性质即可求得至少有两名骑手选择方案()a 的概率;(3)设骑手每日完成外卖业务量为X 件,分别表示出方案()a 的日工资和方案()b 的日工资函数解析式,即可计算两种计算方式下的数学期望,并根据数学期望作出选择. 解:(1)设事件A 为“随机选取一天,这一天该快餐店的骑手的人均日外卖业务量不少于65单”.根据频率分布直方图可知快餐店的人均日外卖业务量不少于65单的频率分别为0.2,0.15,0.05,∵020*******++=...., ∴()P A 估计为0.4.(2)设事件′为“甲、乙、丙、丁四名骑手中至少有两名骑手选择方案()a ”, 设事件i C ,为“甲、乙、丙、丁四名骑手中恰有()01234ii =,,,,人选择方案()a ”, 则()()()41310144212163211111333818127P B P C P C C C ⎛⎫⎛⎫⎛⎫=--=--=--= ⎪ ⎪ ⎪⎝⎭⎝⎭⎝⎭, 所以四名骑手中至少有两名骑手选择方案()a 的概率为1127. (3)设骑手每日完成外卖业务量为X 件, 方案()a 的日工资()11002,*Y X X N =+∈,方案()b 的日工资()215054*15055454*X X N Y X X X N ≤∈⎧=⎨+->∈⎩,,,,,所以随机变量1Y 的分布列为()1160005180005200022200324002260015280005224E Y =⨯+⨯+⨯+⨯+⨯+⨯+⨯=.......;同理,随机变量2Y 的分布列为()21500318003230022800153300052035E Y =⨯+⨯+⨯+⨯+⨯=.......∵()()21EY E Y >,∴建议骑手应选择方案()a . 点评:本题考查了频率分布直方图的简单应用,独立重复试验概率的求法,数学期望的求法并由期望作出方案选择,属于中档题.21.已知函数()()ln 1f x m x x =+-,()sin g x mx x =-.(1)若函数()f x 在()0+∞,上单调递减,且函数()g x 在02,上单调递增,求实数m 的值;(2)求证:()()21111sin11sin 1sin 1sin 12231e n n ⎛⎫⎛⎫⎛⎫+++⋯+<⎪ ⎪⎪ ⎪⨯⨯-⨯⎝⎭⎝⎭⎝⎭(*n N ∈,且2n ≥).答案:(1)1;(2)见解析(1)分别求得()f x 与()g x 的导函数,由导函数与单调性关系即可求得m 的值; (2)由(1)可知当0x >时,()ln1x x +<,当02x π<<时,sin x x <,因而()()*111sin1sinsin sin 0,213,221n N n n n⋯>∈≥⨯⨯-⨯,,,,,构造()()111ln 1sin11+sin 1+sin 1sin 12231n n ⎡⎤⎛⎫⎛⎫⎛⎫+⋯+⎢⎥ ⎪ ⎪⎪ ⎪⨯⨯-⨯⎝⎭⎝⎭⎢⎥⎝⎭⎣⎦,由对数运算及不等式放缩可证明()()1111ln 1sin11+sin 1+sin 1sin 2212231n n n ⎡⎤⎛⎫⎛⎫⎛⎫+⋯+=-<⎢⎥ ⎪ ⎪⎪ ⎪⨯⨯-⨯⎝⎭⎝⎭⎢⎥⎝⎭⎣⎦,从而不等式可证明. 解:(1)∵函数()f x 在()0+∞,上单调递减, ∴()101mf x x'=-≤+,即1m x ≤+在()0+∞,上恒成立, ∴1m ,又∵函数()g x 在02,上单调递增,∴()cos 0g x m x '=-≥,即cos m x ≥在02,上恒成立,m 1≥,∴综上可知,1m =.(2)证明:由(1)知,当1m =时,函数()()ln 1f x x x =+-在()0+∞,上为减函数,()sin g x x x =-在02,上为增函数,而()()00,00f g ==,∴当0x >时,()ln 1x x +<,当02x π<<时,sin x x <. ∴()()*111sin1sinsin sin 0,213,221n N n n n⋯>∈≥⨯⨯-⨯,,,, ∴()()111ln 1sin11+sin 1+sin 1sin 12231n n ⎡⎤⎛⎫⎛⎫⎛⎫+⋯+⎢⎥ ⎪ ⎪⎪ ⎪⨯⨯-⨯⎝⎭⎝⎭⎢⎥⎝⎭⎣⎦()()111ln 1sin1ln 1+sin ln 1+sin ln 1sin 12231n n ⎛⎫⎛⎫⎛⎫=+++⋯++ ⎪ ⎪ ⎪ ⎪⨯⨯-⨯⎝⎭⎝⎭⎝⎭ ()111sin1sinsin sin 12231n n <+++⋯+⨯⨯-⨯()11111111111122312231n n n n ⎛⎫⎛⎫⎛⎫<+++⋯+=+-+-+⋯+- ⎪ ⎪ ⎪⨯⨯-⨯-⎝⎭⎝⎭⎝⎭122n=-< 即()()111ln 1sin11+sin 1+sin 1sin 212231n n ⎡⎤⎛⎫⎛⎫⎛⎫+⋯+<⎢⎥ ⎪ ⎪⎪ ⎪⨯⨯-⨯⎝⎭⎝⎭⎢⎥⎝⎭⎣⎦, ∴()()()2*1111sin11+sin 1+sin 1sin ,212231e n N n n n ⎛⎫⎛⎫⎛⎫+⋯+<∈≥⎪ ⎪⎪ ⎪⨯⨯-⨯⎝⎭⎝⎭⎝⎭,. 点评:本题考查了导数与函数单调性关系,放缩法在证明不等式中的应用,属于难题. 22.在直角坐标系xOy 中,直线l 的方程为0x y a -+=,曲线C 的参数方程为22cos 22sin x y αα=+⎧⎨=+⎩(α为参数).以坐标原点O 为极点,x 轴正半轴为极轴建立极坐标系.(1)求直线l 和曲线C 的极坐标方程;(2)若射线6πθ=与l 的交点为M ,与曲线C 的交点为A ,B ,且4OA OB OM +=,求实数a 的值.答案:(1)l :cos sin 0a ρθρθ-+=,C :24cos 4sin 40ρρθρθ--+=(2)12a =- (1)先消去参数得到C 的普通方程,然后利用cos x ρθ=,sin y ρθ=分别代入,得到直线和曲线C 的极坐标方程.(2)在极坐标系中,设1π,6M ρ⎛⎫ ⎪⎝⎭,2π,6A ρ⎛⎫ ⎪⎝⎭,3π,6B ρ⎛⎫ ⎪⎝⎭,将π6θ=代入24cos 4sin 40ρρθρθ--+=,然后利用韦达定理求解.解:(1)将cos x ρθ=,sin y ρθ=代入方程0x y a -+=中,得到直线l 的极坐标方程为cos sin 0a ρθρθ-+=;曲线C 的普通方程为()()22224x y -+-=,即224440x y x y +--+=, 所以曲线C 的极坐标方程为24cos 4sin 40ρρθρθ--+=.(2)在极坐标系中,可设1π,6M ρ⎛⎫ ⎪⎝⎭,2π,6A ρ⎛⎫ ⎪⎝⎭,3π,6B ρ⎛⎫ ⎪⎝⎭, 将π6θ=代入24cos 4sin 40ρρθρθ--+=,得()2240ρρ-+=,∴232ρρ+=,∵4OA OB OM +=,∴1ρ=即1π,26M ⎛⎫ ⎪ ⎪⎝⎭,将1π,26M ⎛⎫ ⎪ ⎪⎝⎭代入cos sin 0a ρθρθ-+=,得()111sin cos 222a ρθθ=-=⨯=-. 点评:本题主要考查参数方程,普通法方程极坐标方程间的转化以及直线与曲线的位置关系,还考查了运算求解的能力,属于中档题.23.已知不等式112x x ++-≤的解集为{}x a x b ≤≤.(1)求实数a 、b 的值;(2)设0m >,0n >,且满足122a b m n-=,求证:1212m n ++-≥. 答案:(1)1a =-,1b =(2)见解析(1)利用绝对值的几何意义,去绝对值求解.(2)由(1)得到1122m n+=,利用三角不等式转化为1212m n m n ++-≥+,再利用基本不等式求解.解:(1)原不等式等价于①122x x <-⎧⎨-≤⎩,∴x ∈∅; ②1122x -≤≤⎧⎨≤⎩,∴11x -≤≤; ③122x x >⎧⎨≤⎩,∴x ∈∅. 所以原不等式的解集为{}11x x -≤≤,∴1a =-,1b =.(2)∵122a b m n -=,∴1122m n+=, ∴()()1211212m n m n m n ++-≥++-=+()111122222222n m m n m n m n ⎛⎫⎛⎫=+⋅+=++≥ ⎪ ⎪⎝⎭⎝⎭, 当且仅当22n m m n =,即1m =,12n =时取等号, ∴1212m n ++-≥.点评:本题主要考查绝对值不等式的解法以及三角不等式和基本不等式的应用,还考查了运算求解的能力,属于中档题.。

专题062020年全国高考试题(I、II、III)书面表达(解析版)

专题062020年全国⾼考试题(I、II、III)书⾯表达(解析版)2020年全国⾼考试题(I、II、III)试题及经典模拟题分类汇编之书⾯表达2020年全国⾼考试题(I、II、III)1.【2020·全国新课标I】你校正在组织英语作⽂⽐赛。

请以⾝边值得尊敬和爱戴的⼈为题,写⼀篇短⽂参赛,内容包括:1. ⼈物简介;2. 尊敬和爱戴的原因。

注意:1. 词数100左右;2. 短⽂题⽬和⾸句已为你写好。

____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________ 【答案】The person I respectWe have a lot of respectable people around us. They may be our teachers, parents or one of our elders. As for me, my father is the person I respect most. My father is a teacher who loves his work and his students very much. He works very hard every day but he will also spare some time to accompany me and share many funny things with me about his work.When I come across the problems of learning in my study, my father will listen to me patiently and encourage me to overcome the difficulties bravely. He achieved a lot in his work, respected by his students. So, in my mind my father is the person I respect most and I love him deeply.【解析】本篇书⾯表达属于应⽤⽂。

2020届高考英语模拟特效卷 第三卷

2020届高考英语模拟特效卷第三卷1、阅读下面短文,从每题所给的四个选项(A,B,C和D)中,选出最佳选项。

A Guide to the UniversityFoodThe TWU Cafeteria is open 7 a.m. to 8 p.m. It serves snacks(小吃), drinks, ice cream bars and meals. You can pay with cash or your ID cards. You can add meal money to your ID cards at the Front Desk. Even if you do not buy your food in the cafeteria, you can use the tables to eat your lunch, to have meetings and to study.If you are on campus in the evening or late at night, you can buy snacks, fast food, and drinks in the Lower Café located in the bottom level of the Douglas Centre. This area is often used for entertainment such as concerts, games or TV watching.RelaxationThe Globe, located in the bottom level of McMillan Hall, is available for relaxing, studying, cooking, and eating. Monthly activities are held here for all international students. Hours are 10 a.m. to 10 p.m., closed on Sundays.HealthLocated on the top floor of Douglas Hall, the Wellness Centre is committed to physical, emotional and social health. A doctor and nurse is available if you have health questions or need immediate medical help or personal advice. The cost of this is included in your medical insurance. Hours are Monday to Friday, 9 a.m. to noon and 1:00 to 4:30 p.m.Academic SupportAll students have access to the Writing Centre on the upper floor of Douglas Hall. Here, qualified volunteers will work with you on written work, grammar, vocabulary, and other academic skills. You can sign up for an appointment on the sign-up sheet outside the door: two30-minute appointments per week maximum. This service is free.1.What can you do in the TWU Cafeteria?A.Do homework and watch TVB.Buy drinks and enjoy concertsC.have meals and meet with friendsD.Add money to your ID and play chess2.Where and when can you cook your own food?A.The McMillan Hall, Sunday.B.The Lower Café, SundayC.The TWU Cafeteria, FridayD.The Globe, Friday3.The Guide tells us that the Wellness Centre _________.A.is open six days a weekB.gives advice on mental healthC.trains students in medical careD.offers services free of charge4.How can you seek help from the Writing Center?A.By filling in a sign-up formB.By applying onlineC.By calling the centerD.By going to the center directly2、One evening last summer, when I asked my 17-year-old son, Ray, for help with dinner, his response surprised me, “What’s a colander(漏勺)?” he asked.I could only blame myself. Nobody’s hands went in the sauce except my own. But that night, as I explained with a touch of panic that a colander is the thing with holes in it, I wondered what else I hadn’t prepared Ray for. I felt confident that I’d raised a self-reliant boy, as we all try to do. But could he boil water? Sew on a button? Wash his clothes without turning them pink? No, no and no. Suddenly it hit me: He’d be leaving the house in a year to attend college. No way was I going to set a spoiled prince into the world.As parents, while we focus on our child’s confidence and character, we perhaps don’t always consider th at we are also raising someone’s future roommate, boyfriend, husband, or father. I wanted to know that I’d raised a boy who would never ask the woman in his life, “What’s for dinner?” So I came up with a plan: I would offer Ray a private home economics cou rse. I was delighted to find that he didn’t say no.For two hours, three days a week, Ray was all mine. One day, as his tomato sauce reduced on the stove, he washed and seasoned a chicken for toasting. Then he rolled out the piecrust(馅饼皮)and filled it with apples, all while listening to my explanation on the importance of preheating an oven.Three of my four grandparents were tailors, so Ray was genetically programmed to quickly master the basics, like mending a split seam or refastening a button. One day we covered Advanced Laundry, in which I taught him never to mix a red sweatshirt with white shirts or put sweaters in the dryer. I knew that he would rather have been shooting hoops in the driveway than learning to mend socks with his mother -- he tried to beg off sewing lessons, even though Iinsisted that one day, someone would find the sight of him fixing his own shirt very attractive -- but it couldn’t be denied that he was learning, and more than just housekeeping. “I appreciate more what you do as a mo m,” he told me one day.Ray now understands the finer points of cooking, and more important, he realizes there’s nothing masculine(男子气的)about being helpless. Not only can he make his own dinner, he can make it for his family, too. That’s what I call a man.1.Hearing her son’s question, the author felt _______.A.shockedB.angryC.disappointedD.calm2.We can learn from the text that Ray ________.A.made great progress in cookingB.preferred sewing to cookingC.was unwilling to take the course at firstD.always thought it attractive to do housework3.The underlined part “more than just housekeeping” shows that Ray _______.A.fell in love with houseworkB.did other work in the houseC.acknowledges the author’s effortsD.began to be more independent4.What would be the best title for the text?A.Are Women Programmed for Housework?B.Should Boys Be Involved in Housework?C.I’m Proud I’ve Raised a Curious SonD.A Present for My Future Daughter-in-law3、In mice, scientists have used a variety of drugs to treat brain disorders including murine versions of Alzheimer’s disease(阿尔茨海默氏病)and depression. But in people, these same treatments usually fail. And now researchers are beginning to understand why. A detailed comparison of the cell types in mouse and human brain tissue found subtle but important differences that could affect the response to many drugs, a team reported on Wednesday.“If you want to develop a drug that targets a specific receptor in a specific disease, then these differences really matter,” s ays Christ of Koch, an author of the study and chief scientist andpresident of the Allen Institute for Brain Science in Seattle.One key difference involved genes that cause a cell to respond to the chemical messenger serotonin (血淸素), says Ed Lein, a stu dy author and investigator at the institute. “They’re expressed in both mouse and human,but they’re not in the same types of cells,” Lein says.Now, researchers have a way to make sure the types of cells involved in a particular disease work the same way in people as in an animal model, Koch says.“The technology finally caught up with what we’ve been needing to do for probably over 40 years," says Tomasz Nowakowski, an assistant professor of anatomy at the University of California, San Francisco who co-wrote an editorial that accompanied the study.To compare mouse and human brain cells, researchers first analyzed sixteen thousand human brain cells taken from the middle temporal gyms, a part of the cortex(大脑皮层), the brain's outermost layer. Then they looked at cells taken from the same area of a mouse brain.“In one sense, they are remarkably similar,” Koch says, noting that both mice and human had about 100 different types of cells in this region of the brain. But a close comparison of 75 of these brain cell types revealed small differences.“Those cells are the immune(免疫的)cells of the brain,”Nowakowski says. “ And you might imagine that studies or insights into neuroimmune (神经免疫)disorders, for example, might be vastly affected by this difference.“ And that could be one reason experimental Alzheimer’s drugs have helped mice, but not people.1.Why do the researchers compare mouse and human brain cells?A. To develop some kinds of drugs.B.To improve accuracy in treatment.C. To find a way to cure brain disorders.D.To look for the reason for some medicalfailures.2.What makes many drugs effective for mice but not for people?A. The effects of different parts of the genes.B.The response of the chemical materials.C. Small but important differences in brain cells.D.Different gene expressions of different cells.3.What do the researchers expect of the result they have found?A. It’ll solve the present problem soon.B.It’ll give them the proper assistance to further study.C. It'll be very helpful for all diseases.D. It’ll help speed up the study of the genes.4.Where is this text most likely from?A. A diary.B. A guidebook.C. A novel.D. A newspaper.4、It is becoming increasingly important for researchers to closely monitor our ocean life. However,observing sea creatures up close is almost impossible since human presence scares them. Now, thanks to The Soft Robotic Fish, also known as SoFi, researchers may be able to keep a close eye on the sea creatures.Built by MIT Computer Science and Artificial Intelligence Laboratory (CSAIL) , the white remote-controlled robot resembles the real fish, complete with a tail that waves from side to side. Though not the first autonomous underwater vehicle( AUV) created to monitor the ocean, SoFi settles many of the problems that have blocked the usefulness of previous robot fish.Previous AUVs have had to be linked to boats because radio frequency communications don't work well underwater. To overcome the problem, Director of the CSAIL Daniela Rus and her team used sound waves. The technology can travel greater distances allowing divers to pilot SoFi from up to 50 feet away.Also limiting the usefulness of traditional AUVs is the risk of collision. With the outside made of soft silicone(硅树脂) rubber and flexible plastic that keeps its inbuilt electronics dry, SoFi poses no such danger. "Collision avoidance often leads to unnecessary movement,since the robot has to settle for a collision-free path," says Rus. "In contrast, a soft robot is not only more likely to survive a collision but also could use it as information to form a more workable movement plan next time around."During test dives, SoFi moved alongside the ocean life at depths of 50 feet for up to 40 minutes at a time, taking photos and making videos. The researchers say sometimes the fish would swim alongside the strange-looking robot-fish out of curiosity, while at other times they took no notice of its existence.While SoFi presently only records video, future versions will include sensors. The researchers also hope to make it more autonomous. "We imagine someday it might help us uncover more secrets from the amazing underwater world that we know so little about," says Rus.1.What can we learn about SoFi?A.Its tail is flexible.B.It is the first AUV.C.It is closely controlled.D.Its presence scares sea animals.2.What can be learned from paragraph 3?A.Sound waves travel faster than radio.B.Radio does not work well underwater.C.Previous AUVs use radio to communicate.D.A boat travels along with SoFi on the water.3.How does SoFi differ from traditional AUVs?A.It is controlled above.B.It can avoid a collision.C.It can smartly adjust its movement plan.D.It is set for a collision-free path.4.What happened during test dives?A.The fish tried to avoid SoFi.B.SoFi didn't disturb the real fish.C.SoFi swam at depths of 50 meters.D.SoFi monitored the fish population.5、根据短文内容,从短文后的选项中选出能填入空白处的最佳选项。

2021版全国100所名校高三测试示范卷英语试题(五)含答案

2021版全国100所名校高三测试示范卷英语试题(五)含答案第一部分听力(共两节,满分30分)第一节(共5小题;每小题1.5分,满分7.5分)听下面5段对话。

每段对话后有一个小题,从题中所给的A、B、C三个选项中选出最佳选项,并标在试卷的相应位置。

听完每段对话后,你都有10秒钟的时间来回答有关小题和阅读下一小题。

每段对话仅读一遍。

1. What are the speakers talking about? A. A dinner party. dinner.2. Why does the man congratulate the woman? A. She ranked Number 1 in the exams. B. She was popular in her class. C. She quit the exam.3. What does the man mean? A. Pizza tastes terrible. expensive.4. What may be the weather like at the weekend? A. Sunny.B. Rainy.C. Snowy.B. Pizza was once cheap.C. Pizza is alwaysB. A plan for the night.C. A movie about5. What does the woman advise the man to do? A. Turn down the music.B. Go to bed early.C. Set an alarm.第二节(共15小题;每小题1.5分,满分22.5分)听下面5段对活或独白。

每段对话或独白后有几个小题,从题中所给的A、B、C三个选项中选出最佳选项,并标在试卷的相应位置。

听每段对话或独白前,你将有时间阅读各个小题,每小题5秒钟;听完后,各小题将给出5秒钟的作答时间。

全国100所名校单元测试示范卷(高三):英语 全国人教17

全国100所名校单元测试示范卷·高三·英语卷(十七)第十七套英语7Units3~5(120分钟150分)第Ⅰ卷第一部分听力(共两节,满分30分)第一节(共5小题;每小题1.5分,满分7.5分)听下面5段对话。

每段对话后有一个小题,从题中所给的A、B、C三个选项中选出最佳选项,并标在试卷的相应位置。

听完每段对话后,你都有10秒钟的时间来回答有关小题和阅读下一小题。

每段对话仅读一遍。

1.Where does the conversation probably take place?A.In a hotel.B.In a store.C.In a restaurant.2.What does the man want to get?A.A computer.B.Some beer.C.Some cigarettes.3.How can the man get to the nearest hospital directly?A.Taking a T-9.B.Walking two blocks.C.Taking a T-15.4.What s the probable relationship of the two speakers?A.Mother and son.B.Doctor and patient.C.Teacher and student.5.What does the man eat at last?A.An apple.B.A banana.C.A pear.第二节(共15小题;每小题1.5分,满分22.5分)听下面5段对话或独白。

每段对话或独白后有几个小题,从题中所给的A、B、C三个选项中选出最佳选项,并标在试卷的相应位置。

听每段对话或独白前,你将有时间阅读各个小题,每小题5秒钟;听完后,各小题将给出5秒钟的作答时间。

每段对话或独白读两遍。

听第6段材料,回答第6、7题。

  1. 1、下载文档前请自行甄别文档内容的完整性,平台不提供额外的编辑、内容补充、找答案等附加服务。
  2. 2、"仅部分预览"的文档,不可在线预览部分如存在完整性等问题,可反馈申请退款(可完整预览的文档不适用该条件!)。
  3. 3、如文档侵犯您的权益,请联系客服反馈,我们会尽快为您处理(人工客服工作时间:9:00-18:30)。
相关文档
最新文档