I (restriction) myself to smoking two cigarettes a day.

设N_A为阿伏加德罗常数的值，则下列说法正确的是（   ）

All the medical (全体工作人员) who took part in the fight against the SARS are hard-working .

以下有关物质的质量分数和物质的量浓度的叙述正确的是（   ）

定义运算=ad-bc ，则符合条件=4+2i的复数z为（　　）

阅读下面的文字，完成下面小题。

材料一：

此次卖货郎携手乐抖文化传媒，旨在借助互联网产业发展契机，利用卖货郎多年来建立的已程盖全国23个省市的农村立体化销售网络，尤其是正在升级运营的市县级运营中心和乡镇村电子商务服务站，积极把握以直播为代表的流量经济时代的风口机遇，借助快速便捷的5G直播平台，通过网红孵化、直播带货、电商整合、网络营销策划等对卖货郎现有产品和营销进行立体化商业模式再造。

在卖货郎执行总裁张玉生看来，直播电商比起传统电商在客户消费者吸引力方面更胜一筹。直播电商的模式主要是主播通过视频的形式对产品进行讲解以及示范，让消费者全面地了解产品或服务。直播电商维度较传统电商更加丰富，能消除消费者在信息不对称的情况下存在的疑虑。

“这才是农村电商的风口，”张玉生激动地表示，“卖货郎通过此次入股‘乐料’，可有效地实现电商下沉，拉近农民与市场的距离，高效地将2万多名‘货郎’和‘货娘’经过培训成为网红，更加高效地把农产品通过直播带货的形式带到千家万户，这对于设立服务网点的2000多个乡镇来说有着非常重要的意义。”

（摘编自《农村电商卖货郎携手乐抖直播平台搞活城乡农产品互联网销售通道》）

材料二：

材料三：

数字经济加速发展，新一代信息技术创新空前活跃，不断催生新模式新业态，为数字乡村发展创造了前所未有的机遇。在这一背景下形成的由党委领导、政府推动、电商搭台，农民受益的新型农村社交电商模式迅速发展，开辟了一条助力农民增收，农业增效，精准脱贫可持续发展的新路子，借助数字乡村建设推动乡村振兴提速，助力脱贫攻坚。

电商是新型经济体，更是农村经济转型的重要成果。电商赋能乡村，要以“新基建”为牵引，遵循“市场主导、政府引导”的准则，加快数字乡村的信息基础设施建设，大幅提升乡村互联网设施的联通水平，完善乡村信息终端和服务供给。提速乡村交通基础设施的联网升级，让看得见的交通网络与看不见的信息网络联手，形成上下联动、广泛覆盖、及时准确的物流信息网络，打通物流服务“最先和最后一公里”。利用大数据打造大数据销售网络平台，通过大数据精准计算，将市场需求精准化，实现乡村电商的有效供给。给予乡村资源的赋能，催生农产品销售的乘法效应，最大限度扩大农产品销售渠道，实现城市消费反哺农村，助力农民增收致富。

（摘编自《数字乡村助力脱贫攻坚》）

材料四：

农村电商经济正给中国农业带来一系列积极变化。据了解，社交电商正在成为县城经济新的增长点，直播带货、微商、社区拼购等新模式、新业态在县城蓬勃兴起，手机变成了“新农具”，数据变成了“新农资”，直播变成了“新农活”。尤其是此次疫情期间，农村直播电商空前火爆，县长、镇长、网红纷纷开启“带货模式”，不少农产品上线不久就被抢购一空。

此外，人民网电商研究院联合中国农业大学专家课题组发布的《中国农村电商物流发展报告》预测，今年的疫情将催生新的消费习惯，也将倒逼农村电商产业链大变革。作为“新基建”服务经济发展和社会民生的重要部分，智能供应链将在智慧农业、产业带动、扶贫脱贫以及物流普惠上发挥基础性作用。

农村电商虽然近年来发展迅猛，但也遇到了一些问题。对此，商务部副部长王炳南表示，针对产业供应链水平差、物流成本高、人才缺少等农村电商目前存在的问题，将采取多方面措施予以解决，包括加大对返乡农民工，大学生和返乡的转业军人等培训力度，打造农村电商队伍；引导农村商贸企业与电商深度融合，支持流通企业在农村地区开展第三方配送服务，建设线上线下融合的农村现代流通网络等。

（摘编自《网民破2.5亿  农村电商迎来发展良机》）

任务型阅读

    Do you have any problem with time? Start doing these and you will see the difference.

●Write it down

    Don't rely on your memory to keep track of every little detail. Write down the things you need to do in a small notebook, or use online tool to create and update your “to-do” list.

●

    Working for long periods without a break can waste your time. It is more efficient to work or study for a shorter period of time, take a break, and then go back to work. You may get more done in tow focused 45-minute sessions.

● One thing at a time

    Do one thing at a time, and do it well. As the Chinese proverb says, “One cannot manage too many affairs. Like pumpkins in the water, one pops up while you try to hold down the other.”

● Schedule email time

    On your cell phone you get a notification every time someone sends you an email. If so, you have to check your email many, many times a day. Schedule time to check your email. It doesn't matter when.

● Choose to say “No”.

    It's easy to become overwhelmed if we say “yes” to everything. Think about the task before you commit to it. Do you need to do it? Can someone else do it? Avoid saying “yes” to every request.

● Keep a goal journal

    Write down your goals in a journal and evaluate them regularly. Mark your progress for each goal. Be sure you take the necessary step to achieve your goals.

A. Make a list first B. Don't skip the breaks C. Turn that notification off D. Memory is not always accurate E. Don't forget to focus on your task F. This takes time away from more important tasks G. Every time we switch from one task to another, we lose focus

若线性方程组的增广矩阵为、解为，则c₁-c₂=  ．

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作文。文中共有处错误，每句中最多有两处。每处错误仅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（∧),并在其下面写出该加的词。

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）.毎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。

    In recent years, there are more and more Confucius Instiutcs being built all over the world, that shows our Chinese culture has been become much more popular than ever. As one of the four ancient civilizations, China has long history and creates many splendid cultures. The ancient Chinese culture once had powerful influences in the world's civilization, especially in Japan, South Korean and other Asian country. The Chinese culture is slow accumulaled in the whole Chinese history, made it colorful and brilliant. If one want to know or study Chinese culture more deeply, he or she must spend much time. Therefore he or she can only get the tip of an iccberg.

阅读理解

    The African elephant, the largest land animal remaining on earth , is of great importance to African ecosystem(生态系统). Unlike other animals, the African elephant is to a great extent the builder of its environment. As a big plant-eater, it largely shapes the forest-and-savanna(大草原)surroundings in which it lives, therefore setting the terms of existence for millions of other animals that live in its habitat(栖息地).

    It is the elephant's great desire for food that makes it a disturber of the environment and an important builder of its habitat. In its continuous search for the 300 pounds of plants it must have every day, it kills small trees and underbushes, and pulls branches off big trees. This results in numerous open spaces in both deep tropical forests and in the woodlands that cover part of the African savannas. In these open spaces are numerous plants in various stages of growth that attract a variety of other plant-eaters.

    Take the rain forests for example. In their natural state, the spreading branches overhead shut out sunlight and prevent the growth of plants on the forest floor. By pulling down trees and eating plants, elephants make open spaces, allowing new plants to grow on the forest floor. In such situations, the forests become suitable for large hoofed plant-eaters to move around and for small plant-eaters to get their food as well.

    What worries scientists now is that the African elephant has become an endangered species. If the elephant disappears, scientists say, many other animals will also disappear from vast areas of forest and savanna, greatly changing and worsening the whole ecosystem.

A lot of Tang poetry has been (翻译)into English.

根据短文内容，从短文后的选项中选出填入空白处的最佳选项。选项中有两项为多余选项。

    What do the world's most successful people all have in common?

    By examining the work habits of over 150 greatest writers and artists and scientists, the researchers including Standford Professor Jeffrey Preffer found that high achievers like Robert Moses turn out to be all alike:

    Busy! Busy!

     In a study of general managers in industry, John Kotter reported that many of them worked 60 to 65 hours per week—which translates into at least six 10-hour days. The ability and willingness to work difficult and tiring hours has characterized many powerful figures. Energy and strength provide many advantages for those seeking to build power.  

    Just Say No!

    The difference between successful people and very successful people is that very successful people say "no" to almost everything. And that's what gives them the time to accomplish so much.  And focus means saying "no" to a lot of distractions(分神).  

    Know What You Are!

    Ignore your weakness and keep improving your strengths. Don't waste time exploring skill areas where you have little competence. Instead, focus on—and build on—your strengths.

    Create Good Luck!

    Luck is not magical—there is a science to it. Richard Wiseman studied lucky people for his book Luck Factor, and broke down what they do right.  By being more outgoing, open to new ideas, following the feeling that something is true, being optimistic, lucky people create possibilities.  

    Does applying these principles to your life actually work? Wiseman created a "luck school" to test the ideas—and it was a success. In total, 80 percent of people who attended Luck School said that their luck had increased.

A. Achievement requires focus.

B. On average, these people reported that their luck had increased by more than 40 percent.

C. Spend enough time to improve your weakness.

D. High achievers never stop working and they never lose a minute.

E. This means knowing who you are and what you are good at.

F. Busy people are more likely to be lucky.

G. Certain personality types are luckier because they behave in a way that offers the chance for good opportunities.

The lawyer witnessed the poor man at the court.

她以前从来没有见过和罗伯特一样打网球打得这么好的人。

Never before   anybody who can play tennis as well as Robert.

The problem was how to get rid of her without causing o(冒犯).

同温同压下，a g甲气体和2a g乙气体所占的体积之比为1： 2，根据阿伏加德罗定律判断，下列叙述不正确的是(　　)

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作文。文中共有10处语言错误，每句中最多有两处。每处错误仅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(∧)，并在其下面写出该加的词。

删除：把多余的词用斜线(\)划掉。

修改：在错的词下画一横线，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。

    Thank you for your letter. To tell you the truth, I've thought a lot of about whether you should buy a laptop help you with your study. In my opinion, you'd better not. For one reason, it's very easy for you to develop some bad habit once you have it, such as playing computer games, see movies and so on, which will be a waste of time. For other reason, buying a laptop don't mean you can study well. If you want to make a progress, you need to put your heart into your study but work hard. Whether you had a laptop or not is not the most important. Do you agree to me? Looking forward to your reply!

若行列式 ，则 .

下列化学用语书写不正确的是（　　）

同温同压下，等质量的下列气体所占有的体积最大的是(   )