1 . Nowadays, we can read almost all "truths" on social media sites. But are they really reliable? Sites such as the micro-messaging service, the social networking site and the photo-sharing app Instagram might "misrepresent the real world", according to a study by computer scientists from McGill University and Carnegie Mellon University.

The scientists warn that gathering information about public views and trends from these sites is unwise. There are still large parts of the population who do not take part in social media activities. Also, there's a risk that many social media users are under-represented. Instagram, for example, appeals to younger adults in urban areas while Pinterest is used mainly by females aged 25 to 34. And only 5 percent of the micro-messaging service users are over 65 years old, according to the study. However, this is not the only issue, according to the scientific team. The design of a website can influence how people behave online, creating what the researchers call "Internet bias". For example, micro-blogging sites such as Weibo promote "popular" stories. It saves time for some but it also limits readers' choice of what they see. In the end, many people open those stories and make them more "popular". But it's not because they choose those stories. Rather, it is because the content is right in front of them.

Besides, it's possible that not everyone on your social networks is real. There might actually be a few fake accounts among them. Fake "bots" pretend to be humans and are often included when measuring or predicting human behaviors online.

The findings might be more important than you would think, since many social media studies are used to inform and justify decisions and investments among the public and in industry and government, according to Derek Ruths, an assistant professor of Computer Science at Mc Gill University.

If the team is right, you might have to think carefully next time you say, "It's true, you know; I read it on Weibo."

1. Why does the author mention the micro-messaging and Instagram?

A．Because they are the best social media sites today.

B．Because they are not in favor of the current study.

C．Because the public are sharing truths on these sites.

D．Because information on these sites may not be reliable.

2. How is the passage developed?

A．By giving examples.	B．By making comparisons.
C．By dividing into groups.	D．By analyzing causes.

3. Which word can best describe the author's attitude toward information on social media sites?

A．Ambiguous.

B．Favorable.

C．Disagreeable.

D．Cautious.

4. What's the author's main purpose in writing the passage?

A．To analyze why information gathered from social media sites may not be trustworthy.

B．To remind readers of things they should watch out for when using social media.

C．To point out the advantages and disadvantages of social media.

D．To recommend popular social networking sites for readers.

2 . Throughout history scientists have risked their health and their lives in their search for the truth.

Sir Isaac Newton, the seventeenth century scientist, was very smart, but that didn't stop him from doing   some pretty stupid things. In his laboratory in Cambridge he often did the strangest experiments. Once, while testing how light passes through lenses, he put a long needle into his eye, pushed it to the back, and then moved it around just to see what would happen. Luckily, nothing long-lasting did. On another occasion he stared at the sun for as long as he could bear, to discover what effect this would have on his sight. Again he escaped suffering permanent damage, though he had to spend some days in a darkened room before his eyes recovered.

In the 1750s the Swedish chemist Karl Scheele was the first person to find a way to produce phosphorus. He in fact discovered eight more chemical elements including chlorine , though he didn't get any praise for them. He was a very clever scientist, but his one failing was a curious habit of tasting a little of every substance he worked with. This risky practice finally caught up with him, and in 1786 he was found dead in his laboratory surrounded by a large number of dangerous chemicals, any of which might have been responsible for his death.

Eugene Shoemaker was a respected geologist. He spent a large part of his life studying craters on the moon, and how they were formed, and later did research into the comets of the planet Jupiter. In 1997 he and his wife were in the Australian desert where they went every year to search for places where comets might have hit the earth. While driving in the Tanami desert, normally one of the emptiest places in the world, another vehicle crashed into them and Shoemaker was killed on the spot. Some of his ashes were sent to the moon aboard the Lunar Prospector spacecraft and left there — he is the only person who has had this honor.

1. Which word is similar to the underlined word “permanent” in Paragraph 2?

A．Brief.

B．Lasting.

C．Slight.

D．Ordinary.

2. What do we know about Karl Scheele according to this text?

A．He was killed by tasting phosphorus.

B．He killed himself with some dangerous chemicals.

C．His habit of tasting chemicals might account for his death.

D．He got a large number of honors for discovering many chemical elements.

3. Which statement about Shoemaker is true?

A．He was knocked over and died in a desert.	B．All of his ashes were placed on the moon.
C．One comet of Jupiter was named after him.	D．A spacecraft carrying him traveled around Jupiter.

4. What does the text mainly talk about?

A．Three great scientists' famous experiments.	B．Three great scientists' great achievements.
C．Three great scientists' sacrifice for the truth.	D．Three great scientists' special honors.

3 . These people are studying English. However, they are now facing some problems.

I am Pablo. I work 50 hours a week as a taxi driver, so I talk to people all day. They understand me, but I know I make a lot of mistakes. No one corrects me. My vocabulary is strong. Grammar is my problem. I'm trying to change little by little. For example, I don't use the past tense (时态). I always say, “I drive him to the office this morning” instead of “I drove him to the office this morning”.

My name is Maria Luisa. I'm teaching myself English, and I'm good at grammar. However, it's really difficult to find ways to practice English. I live in an area where everyone speaks my language. My neighbors and friends speak Spanish. I can speak Spanish in the supermarket and at the post office.

I am Li Ping. I understand the grammar and the readings in my class and I think my writing is good, but I'm very nervous when I speak English. I don't want to make any mistakes because I'm afraid people will think that I'm stupid. Also, my pronunciation isn't good. When I speak, people often say, “What? Say that again”.

I am Yoshi. I have been in the United States for one year. I'm studying hard and I know grammar well, but the vocabulary is very difficult. When I listen, I don't understand many of the words. When I try to read, there are three or four new words in every sentence. I feel discouraged.

1. Who may say, “I go to bed late last night”？

A．Pablo.

B．Maria Luisa.

C．Li Ping.

D．Yoshi.

2. What would be the best advice for Maria Luisa?

A．Try to have a wide vocabulary.	B．Develop a good knowledge of grammar.
C．Read as many English books as possible.	D．Make friends with English­speaking people.

3. Why do people find it hard to understand Li Ping's English?

A．She can't pronounce words in English correctly.	B．She speaks at a very fast speed.
C．Her grammar is terrible.	D．Her voice is very low.