互花米草是一种原产于北美的海滩植物，种子可随海浪传播，其茎干密集粗壮，地下根茎发达，耐盐耐淹、抗风浪，能够促进泥沙沉降和淤积，减弱海水交换能力。1979年，我国从美国引进互花米草并种植于河口海岸。完成问题。

17. 我国引进互花米草的主要目的是

A. 保滩护岸B.消除海滩污染C. 增加鱼饵D. 防止航道阻塞

18. 互花米草在沿海迅速繁殖扩张成为入侵物种，其产生的主要影响有

①生物多样性减少②滩涂大量减少

③海水质量下降④滩涂养殖条件改善

A. ①②B.②③C. ①③D. ②④

阅读下面文字，完成下列小题。
当前，世界多极化、经济全球化、文化多样化、社会信息化深入发展，人类社会充满希望。同时，国际形势的不稳定性不确定性更加突出，人类面临的全球性挑战更加严峻，需要世界各国共同应对挑战、迈向美好未来。在百年未有之大变局的今天，大国关系事关全球战略稳定，努力推动大国间的文明对话具有十分重要的时代意义。
世界各大国均拥有丰富多彩的伟大文明。中华文明兼收并蓄，融合了黄河文明、长江文明和北方草原文明，在历史进程中不断与其他各种文明碰撞、交流、融会，为推动世界文明交流做出了巨大贡献。欧洲文明同样极富历史文化底蕴，无论是希腊的雕塑、罗马的万神庙、拜占庭的镶嵌画，还是哥伦布的地理大发现、哥白尼的日心说、伽利略的望远镜，莫不是欧洲文明的奇丽瑰宝。
中国与欧洲各国文明对话源远流长，其成功实践充分证明，不同文明之间能够实现互容互鉴互通。自 2014 年启动中法高级别人文交流机制以来，中法两国在教育、科技、文化、艺术、社会等领域的交流发展迅速，而以此为依托的双边政府交流、民间交往、经贸往来也呈现出蓬勃发展的趋势。近年来，中德全方位战略伙伴关系不断迈上新的台阶，陆续建立了高级别财金对话、外交与安全战略对话、高级别人文交流对话等机制，为各领域合作持续推进提供了动力和保障。中俄两国民众相知相亲的历史举世公认，已经成为了两国关系发展的不竭动力，两国文化在彼此国家的影响力、亲和力和感召力不断提升，已经成为了当今大国之间文明对话的典范。
源于欧洲文明的美国文明，与美洲文明结合，发展成为一种高度的物质文明和精神文明，其文明的迅猛发展，很大程度上基于多元文化的价值观。然而 4 月 29 日，美国国务院政策规划事务主任基伦·斯金纳就中美关系发表谈话，将中美关系界定为“文明较量”，宣称美国正在制定基于“文明冲突”的对华关系框架，从而将中美关系渲染至所谓“文明冲突”的层面。在合作共赢成为时代潮流的 21 世纪，这种“文明冲突论”完全是一种历史的倒退，人类文明的悲哀。
文明的生存和进步离不开交流互鉴，文明只有在交流互鉴中才能不断前行。党的十九大报告指出：“要尊重世界文明多样性，以文明交流超越文明隔阂、文明互鉴超越文明冲突、文明共存超越文明优越。”一个充满自信的文明，其前提是要拥有对其他文明包容欣赏、乐于交流的心态。只有交流互鉴，尊重、包容姹紫嫣红的不同文明，自己的文明才能充满生命力。
2019 年是中美建交40周年。中美交往40年来的教训和启示说明：合则两利，斗则俱伤，唯有合作才是正确选择。在中美利益已经高度融合的今天，在经济全球化深入发展的新时代，中美双方更应该承担大国应承担的特殊责任，摒弃冷战思维，谋求合作共赢。
（选自潘震《大国文明对话的时代意义》，有删改）
【1】下列关于原文内容的理解和分析，不正确的一项是（ ）
A. 身处巨大变局之中，世界各国都拥有深入发展所带来的希望，也都需要应对全球性挑战。
B. 以希腊的雕塑、罗马的万神庙等为代表的欧洲文明同中华文明一样丰富多彩而伟大。
C. 中法两国在科教文艺等人文领域的交流带动了双边政府交流、民间交往和经贸往来。
D. 美国文明，正因为其源于欧洲文明，才得以发展成为一种高度的物质文明和精神文明。
【2】下列对原文论证的相关分析，不正确的一项是（ ）
A. 文章以当今世界希望与挑战并存为立论前提，为大国间的文明对话指明了方向，并由此指向了中美关系问题。
B. 文章采用例证、引证等多种论证方法，有力地证明了当今国际形势下推动大国间文明对话的必要性和可能性。
C. 文章列举了中法、中德、中俄之间文明对话的成功案例，旨在说明中国为世界提供了大国间文明对话的典范。
D. 文章以美国文明蕴含多元文化价值观为依据，坚决反对“文明冲突论”，提倡摒弃冷战思维、谋求合作共赢。
【3】根据原文内容，下列说法正确的一项是（ ）
A. 根据中美交往40年来的教训与启示，如果美国坚持“文明冲突论”，必然会两败俱伤。
B. 如果没有对其他文明包容欣赏的心态，一个文明可以充满自信但无法充满生命力。
C. 美国的“文明冲突论”对其本国而言虽然有利，但无法顺应 21 世纪的时代潮流。
D. 只要坚持在交流中互相借鉴，在合作中谋求共赢，世界各国的文明就能够生存和进步。

What does the woman think of her interview?
A. It was tough. B. It was interesting. C. It was successful.

阅读下面的材料，根据要求写作。
①1919年“巴黎和会”期间，中国作为战胜国提出的取消帝国主义在华一切特权的合理要求，遭到和会拒绝。消息传来，举国震惊。1919年5月4日，北京爆发了以青年学生为主、社会各阶层共同参与的五四运动，这一运动使中国代表最终没有出席巴黎和会的签字仪式。
五四运动，一是救亡，即反对腐败无能的北洋政府；二是启蒙，认为文化落后是导致国家社会落后的根源，对传统文化道德采取割舍的态度，更甚者认为要不看中国书只看外国书。
②(五四运动)是中国人的国家情感存在与力量的突变证明，如果还有什么地方的人对中国人爱国主义的力量和普及程度抱有怀疑态度，那么这种证明就是深切而且令人信服的。
——（美)杜威《中国人的国家情感》
③这种运动是非常的事，是变态的社会里暂时不得已的救急办法，却不可长期存在的。
——胡适《我们对于学生的希望》
五四运动已过去一百年，我们汲取五四精神的营养，也不断对五四运动进行反思。在2019年五四青年节到来之际，请结合以上材料为学校五四青年节活动写一篇不少于800字的演讲稿。
要求:选好角度，确定立意，自拟标题，不要套作，不得抄袭，不得泄露个人信息。

已知椭圆C的方程为，焦距为，直线与椭圆C相交于A，B两点，若，则椭圆C的离心率为
A. B. C. D.

如图，直角三角形ABC为一棱镜的横截面，∠A=90°，∠B=30°。一束光线平行于底边BC射到AB边上并进入棱镜，然后垂直于AC边射出。

（1）求棱镜的折射率；
（2）保持AB边上的入射点不变，逐渐减小入射角，直到BC边上恰好有光线射出。求此时AB边上入射角的正弦。

人在恐惧、严重焦虑和紧张等情况下，肾上腺素分泌增多，表现出警觉性提髙、反应灵敏、呼吸频率加快、心跳加速等特征。下列相关说法错误的是

A．恐惧、严重焦虑和紧张等情况导致肾上腺素分泌增多的过程属于神经调节

B．肾上腺素作用的靶细胞包括心肌、肺和肝脏等处的细胞

C．肾上腺素分泌增多会导致血糖浓度迅速降低

D．较长时间的恐惧和焦虑会导致人体免疫力下降

某学习小组进行精确测量电阻Rx的阻值的实验，有下列器材供选用：
A.待测电阻Rx（约300Ω）
B.电压表V（3V，内阻约3kΩ）
C.电流表A1（10mA，内阻约10Ω）
D.电流表A2（20mA，内阻约5Ω）
E.滑动变阻器R1（0~20Ω，额定电流2A)
F.滑动变阻器R2（0~2000Ω，额定电流0.5A)
G.直流电源E(3V，内阻约1Ω）
H.开关、导线若干
（1）甲同学根据以上器材设计成用伏安法测量电阻的电路，并能满足Rx两端电压能从0开始变化进行多次测量。则电流表应选择________（填“A1”或“A2”)；滑动变阻器应选择________（填“R1”或“R2”)；并请在虚线框中帮甲同学完成实验原理电路图 _________ 。

（2）乙同学经过反复思考，利用所给器材设计出了如图所示的测量电路，具体操作如下：

①按图连接好实验电路，闭合开关S1前调节滑动变阻器R1、R2的滑片至适当位置；
②闭合开关S1，断开开关S2，调节滑动变阻器R1、R2的滑片，使电流表A1的示数恰好为电流表A2的示数的一半；
③闭合开关S2并保持滑动变阻器R2的滑片位置不变，读出电压表V和电流表A1的示数，分别记为U、I；
④待测电阻的阻值Rx=________；
比较甲、乙两同学测量电阻Rx的方法，你认为哪种方法更有利于减小系统误差?
答：________同学（填“甲”或“乙”)。

下列说法正确的是______.
A.只要知道气体的摩尔体积和阿伏加德罗常数，就可以算出气体分子的体积
B.悬浮在液体中的固体微粒越小，布朗运动就越明显
C.一定温度下，饱和气体的压强是一定的
D.第二类永动机不可能制成是因为它违反了能量守恒定律
E.液晶既有液体的流动性,又具有单晶体的各向异性

黄河某河段因沿线城市扩建等因素而严重污染，近几年随着环境保护力度的加大，该河段生态环境逐渐恢复。请回答下列问题：
（1）河流群落的_____________是区别不同河流群落的重要特征，河流群落中的生物和______________相互作用共同形成河流生态系统。
（2）由于城市污水和工业废水排放过多，河水中N、P含量升高，造成水体富营养化，浮游藻类大量繁殖，引起水体溶氧量迅速下降，进一步造成鱼类等生物死亡，这一过程中存在______反馈调节；该河流在受到污染后难以恢复的原因是______________________，导致生态系统的自我调节能力迅速丧失。专家建议，在水体发绿的初期，适量投放喜欢滤食藻类的鲢鱼来控制藻类数量，体现了生物多样性的________价值。
（3）从能量流动的角度看，河流中以藻类和浮游植物为代表的生态系统成分，在生态系统中的作用是_________________________________________。

下列说法正确的是（　　）

A. 质子的德布罗意波长与其动能成正比

B. 天然放射的三种射线，穿透能力最强的是射线

C. 光电效应实验中的截止频率与入射光的频率有关

D. 电子束穿过铝箔后的衍射图样说明电子具有波动性

如图所示，一匀强磁场磁感应强度为B；方向向里，其边界是半径为R的圆，AB为圆的一直径.在A点有一粒子源向圆平面内的各个方向发射质量m、电量-q的粒子，粒子重力不计．

(1)有一带电粒子以的速度垂直磁场进入圆形区域，恰从B点射出．求此粒子在磁场中运动的时间．
(2)若磁场的边界是绝缘弹性边界(粒子与边界碰撞后将以原速率反弹)，某粒子沿半径方向射入磁场，经过2次碰撞后回到A点，则该粒子的速度为多大?
(3)若R=3cm、B=0.2T，在A点的粒子源向圆平面内的各个方向发射速度均为3×105m／s、比荷为108C／kg的粒子．试用阴影图画出粒子在磁场中能到达的区域，并求出该区域的面积(结果保留2位有效数字)．

已知函数，若函数有三个零点，则实数的取值范围是（ ）
A. B. C. D.

用11.92gNaClO配成100mL溶液，向其中加入0.01mol Na2Sx恰好完全反应，生成Na2SO4和NaCl。
（1）NaClO溶液的物质的量浓度_________mol·L-1。
（2）化学式Na2Sx中的X=____________。

A scientist working at her lab bench and a six-old baby playing with his food might seem to have little in common.After all,the scientist is engaged in serious research to uncover the very nature of the physical world,and the baby is,well, just playing…right?Perhaps,but some developmental psychologists have argued that this “play” is more like a scientific investigation than one might think.
Take a closer look at the baby playing at the table. Each time the bowl of rice is pushed over the table edge, it
falls in the ground---and, in the process, it belongs out important evidence about how physical objects interact ; bowls of rice do not flood in mid-sit, but require support to remain stable. It is likely that babies are not born knowing the basic fact of the universe; nor are they ever clearly taught it. Instead, babies may form an understanding of object support through repeated experiments and then build on this knowledge to learn even more about how objects interact. Though their ranges and tools differ, the baby’s investigation and the scientist’s experiment appear to share the same aim(to learn about the natural world ), overall approach (gathering direct evidence from the world), and logic (are my observations what I expected?).
Some psychologists suggest that young children learn about more than just the physical world in this way---that they investigate human psychology and the rules of language using similar means. For example, it may only be through repeated experiments, evidence gathering, and finally overturning a theory, that a baby will come to accept the idea that other people can have different views and desires from what he or she has. for example, unlike the child , Mommy actually doesn’t like Dove chocolate.
Viewing childhood development as a scientific investigation throws on how children learn ,but it also offers an inspiring look at science and scientists. Why do young children and scientists seem to be so much alike? Psychologists have suggested that science as an effort ---the desire to explore, explain, and understand our world---is simply something that comes from our babyhood. Perhaps evolution provided human babies with curiosity and a natural drive to explain their worlds, and adult scientists simply make use of the same drive that served them as children. The same cognitive systems that make young children feel good about feel good about figuring something out may have been adopted by adult scientists. As some psychologists put it, ”It is not that children are little scientists but that scientists are big children.”
【1】According to some developmental psychologists,
A. a baby’s play is nothing more than a game.
B. scientific research into babies; games is possible
C. the nature of babies’ play has been thoroughly investigated
D. a baby’s play is somehow similar to a scientist’s experiment
【2】We learn from Paragraph 2 that
A. scientists and babies seem to observe the world differently
B. scientists and babies often interact with each other
C. babies are born with the knowledge of object support
D. babies seem to collect evidence just as scientists do
【3】Children may learn the rules of language by
A. exploring the physical world
B. investigating human psychology
C. repeating their own experiments
D. observing their parents’ behaviors
【4】What is themain idea of the last paragraph?
A. The world may be more clearly explained through children’s play.
B. Studying babies’ play may lead to a better understanding of science.
C. Children may have greater ability to figure out things than scientists.
D. One’s drive for scientific research may become stronger as he grows.
【5】What is the author’s tone when he discusses the connection between scientists’ research and babies’ play?
A. Convincing. B. Confused.
C. Confidence. D. Cautious.

请对下面这段新闻报道的文字进行压缩，要求保留关键信息，句子简洁流畅，不超过80个字。

2020年6月3日，国资委召开中央企业助力湖北疫后重振发展视频会议。在视频会议上，国资委表示，支持将武汉纳入区域性国资国企综合改革试验区，打造改革高地，要继续加大力度，推动各项政策措施在湖北早落地、早见效、早受益，把政策优势转化为发展优势，更好地助力湖北疫后重振。在视频会议现场，央企和湖北省签署72个项目，在原定今年对湖北计划总投资3900亿元基础上，将新增投资超过3200亿元。

假定英语课上老师要求同桌之间交换修改作文，请你修改你同桌写的以下短文。短文中共有 10 处错误， 每句中最多有两处。错误涉及一个单词的增加、删除或修改。
增加：在缺词处加一个漏字符号(Λ),并在此符号下面写出该加的词。
删除：把多余的词用斜线(\)划掉。
修改：在错的词下划一横线，并在该词下面写出修改后的词。
注意：1.每处错误及其修改均仅限一词；
2.只允许修改 10 处，多者(从第 11 处起)不计分。
It was a rain and cold night. I finish my evening classes and was about to go back to my house. I got into a taxi and told the driver my destination. To my surprise, the driver made an apology, says he didn't know the way. What come a taxi driver didn't know the way? I was a little of angry. At the moment, an old couple stopped our car. Their destination was the same as me, so he let them in. The two greeted us but the grandpa told the driver the way. From their conversation I knew the driver was a farmer and he has been a taxi driver just for three days.
I'm also new to Zhengzhou. Sometimes I make direction mistakes, but there is always someone can help me. It was cold outside, but I felt real warm.

I was getting ready for bed when the telephone rang unexpectedly. My mind quickly ran ______ the list of family members, but the voice on the other end of the line was only ______ familiar. “Lindy, this is Leslie,” she said. I didn’t know Leslie very well, so I was a little ______ that she would be calling me at 11:00 pm. I was afraid that it would be something really ______ to cause her to reach out to someone she ______ knew. However, she asked me a most ______ question. “Do you have any room for a turkey in your freezer?” she asked. “Sure,” I responded, feeling quite confused. My family was at the bottom of our food supply. “I will ______ when I get to your house,” Leslie replied.
We quickly ______ blue jeans from our nightclothes and prepared to meet her outside ______ the doorbell wouldn’t wake up our four children. Leslie and her husband came in a huge freezer truck. She explained that her husband serviced a small grocery store that had just lost its lease（ 租 约 ）. They had to ______ all the freezers before midnight. She thought it was a ______ to just throw all this food away so she began to go through her list of ______, dropping off food to anyone who she thought might be ______ to take it. Ours was the last place they planned to stop and anything left would have to be______
Still not fully ______ what had just occurred, I asked her, “When will you be coming back for all this?” Leslie replied, “It is yours! We have been ______ food since 5:00 pm and have ______ our list of contacts. Thanks a lot for helping us out.”
Leslie had no idea that we ______ to buy groceries. By the time the freezer food finally ______, buying groceries was no longer a problem. I admit that I’m still afraid of late night calls, assuming the worst, ______ then I remember that summer night when an acquaintance called me to send me turkeys.
【1】A. into B. across C. through D. after
【2】A. vaguely B. definitely C. reasonably D. hopefully
【3】A. thrilled B. embarrassed C. surprised D. annoyed
【4】A. creative B. impressive C. complex D. awful
【5】A. normally B. barely C. precisely D. frequently
【6】A. strange B. authentic C. fascinating D. tough
【7】A. pause B. explain C. appreciate D. negotiate
【8】A. hunted for B. put aside C. changed into D. took out
【9】A. in that B. as if C. in case D. so that
【10】A. empty B. replace C. fix D. remove
【11】A. success B. shame C. chance D. duty
【12】A. merchants B. rescuers C. contacts D. clients
【13】A. considerate B. generous C. willing D. conscious
【14】A. deleted B. leaked C. swapped D. dumped
【15】A. describing B. understanding C. predicting D. observing
【16】A. submitting B. fetching C. consuming D. delivering
【17】A. packed B. exhausted C. refreshed D. concluded
【18】A. struggled B. managed C. decided D. tended
【19】A. ran out B. went off C. broke down D. caught on
【20】A. for B. or C. and D. but

阅读下面材料，从下面三个题目中任选一题，按要求作答。180字左右
①教育家魏书生曾妙解“人”字。他说，只有两划，一撇一捺。一撇代表长处，一捺代表短处。它告诉我们：金无足赤，人无完人。“人”字上部合并，下部分叉。它告诉我们：人生之路有岔道，有的通向光明，有的通向黑暗，有的通向成功，有的通向失败。“人”字形状告诉我们，人的一生既有上坡路，也有下坡路，不会总在高点上。“人”字一撇一捺还可以表示要相互扶助，相互支持……
请你任选一个汉字（“人”字除外）写一段“妙解”的话。要求：适度想象，合理解说。
②从下面《红楼梦》名言警句中任选三句写一段话。要求：主题明确，语意连贯。
A.身后有余忘缩手，眼前无路想回头。 B.世事洞明皆学问，人情练达即文章。
C.假作真时真亦假，无为有处有还无。 D.机关算尽太聪明，反误了卿卿性命。
E.玉在椟中求善价，钗于奁内待时飞。 F.纵然生得好皮囊，腹内原来草莽。
③“五四运动”一百周年纪念日就要到了。请你从成岗、刘思扬，孙少平、田晓霞等《红岩》《平凡的世界》青年人中任选一人或几人为材料，写一篇纪念五四运动的小诗或抒情文字。要求：感情真挚，富于文采。

研究人员在家蚕中发现一种新的体态类型——短体蚕，用这种家蚕与正常体形家蚕进行杂交实验，结果如表。下列叙述正确的是

A. 可以通过连续自交多代的方式获得纯种短体蚕

B. 短体蚕自交后代出现正常蚕是基因突变的结果

C. 实验一F₁个体随机交配，F₂中短体蚕:正常蚕=2:3

D. 实验二F₁个体随机交配，F₂中正常蚕所占的比例为4/9