1 . On March 7, 1907, the English statistician Francis Galton published a paper which illustrated what has come to be known as the “wisdom of crowds” effect. The experiment of estimation he conducted showed that in some cases, the average of a large number of independent estimates could be quite accurate.

This effect capitalizes on the fact that when people make errors, those errors aren’t always the same. Some people will tend to overestimate, and some to underestimate. When enough of these errors are averaged together, they cancel each other out, resulting in a more accurate estimate. If people are similar and tend to make the same errors, then their errors won’t cancel each other out. In more technical terms, the wisdom of crowds requires that people’s estimates be independent. If for whatever reasons, people’s errors become correlated or dependent, the accuracy of the estimate will go down.

But a new study led by Joaquin Navajas offered an interesting twist (转折) on this classic phenomenon. The key finding of the study was that when crowds were further divided into smaller groups that were allowed to have a discussion, the averages from these groups were more accurate than those from an equal number of independent individuals. For instance, the average obtained from the estimates of four discussion groups of five was significantly more accurate than the average obtained from 20 independent individuals.

In a follow-up study with 100 university students, the researchers tried to get a better sense of what the group members actually did in their discussion. Did they tend to go with those most confident about their estimates? Did they follow those least willing to change their minds? This happened some of the time, but it wasn’t the dominant response. Most frequently, the groups reported that they “shared arguments and reasoned together”. Somehow, these arguments and reasoning resulted in a global reduction in error. Although the studies led by Navajas have limitations and many questions remain, the potential implications for group discussion and decision-making are enormous.

1. What is paragraph 2 of the text mainly about?

A．The methods of estimation.	B．The underlying logic of the effect.
C．The causes of people’s errors.	D．The design of Galton’s experiment.

2. Navajas’ study found that the average accuracy could increase even if ________.

A．the crowds were relatively small	B．there were occasional underestimates
C．individuals did not communicate	D．estimates were not fully independent

3. What did the follow-up study focus on?

A．The size of the groups.	B．The dominant members.
C．The discussion process.	D．The individual estimates.

4. What is the author’s attitude toward Navajas’ studies?

A．Unclear.

B．Dismissive.

C．Doubtful.

D．Approving.

2 . Self-esteem is the ruling view you have of yourself. This includes your beliefs about your inner qualities and how you think others see you.     1     Someone can develop low self-esteem even when they are highly functional and greatly skilled. Understanding this mysterious emotional currency might be the key to unlocking your own self-worth.

People with healthy self-esteem don't need to boast about themselves to others. People with low self-esteem may tell you how much everyone loves them, what a great job they do at work, and how amazing they are at pretty everything under the sun even though they really wonder if it's true. People may see them as obnoxious or “full of themselves”.     2     They are not shy about sharing ideas, including constructive criticisms of others. They also take care of themselves without second-guessing or apologizing. They are the people who we say seem “sure of themselves”.

If you're starting to think you may have low self-esteem, you can work on the way you talk to yourself. When you turn off negative self-talk, you can open the floor to positive reinforcements and access the courage to show different sides of yourself. It isn't going to feel good at first, though. Keep going until it becomes less and less and maybe even a few awkward laughs in the mirror may help.     3    

However, in serious cases of low or even non-existent self-esteem, you may want to call in a professional or a specialist. Good mental health is important, and professionals doing psychotherapy do not pass judgement or give corrections.     4     It is the best way to get at the roots of your real self-esteem problems.

    5     It will take some work but your entire life — from your relationships to your body image to your work habits — will be touched with the kind of power that only comes from someone believing in themselves. This is the hardest part, and the greatest leap. With some changes and support, you can improve your self-esteem and see how everything else changes as a result.

A．Self-esteem is not always rooted in reality, though.

B．You have the power to shape a new self-perception.

C．This encourages you to speak openly without worry.

D．The real test of character is whether they can learn from their mistakes.

E．Self-esteem refers to a person's overall sense of his or her value or worth.

F．People with a healthy level of self-esteem present themselves with a casual confidence.

G．With some practice and persistence, you will win this internal struggle to see your self-worth.

3 . 假定你是李江，你的笔友 Peter来信说，下周他要在课堂上作与“基因编辑”主题相关的介绍展示，希望你能帮助他。你给他写封信，内容包括以下几点：
1.“基因编辑”在生活中的应用；
2.你对该项技术的看法。
注意：1.词数80左右；
2.可以适当增加细节，以使行文连贯。
Dear Peter,

Hearing that you are going to do a presentation on “gene editing” in your class next week,I would like to share with you some relevant information.

________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

I am hopeful that the above information is useful to you.

Yours,

Li Jiang

4 . After I lost my right hand in a car accident two years ago, I began to w________ into myself, believing I would never be able to lead a normal life again. （根据首字母单词拼写）