By now，we are all aware that social media has had a powerful influence on our culture，in business，on the world at large．Social media websites revolutionized the way people communicate and socialize on the Web．However，besides seeing your friends' new baby on Facebook，or reading about Justin Bieber's latest conflict with the law on Twitter，what are some of the real influences？
Social networks offer the opportunity for people to reconnect with their old friends and acquaintances，make new friends，share ideas and pictures，and many other activities．Users can keep pace with the latest global and local developments，and take part in campaigns and activities of their choice．Professionals use social media sites like LinkedIn to improve their career and business development．Students can work together with their peers to improve their academic and communication skills．
Unfortunately，there are a few downsides too to social networking．If you are not careful，immoral people can target you for cyber bullying（網(wǎng)絡(luò)欺凌） and disturbance on social sites．School children，young girls，and women can fall victim to online attacks which can create tension and suffering．If you are a victim of cyber bullying，do not take it lying down，but try to take appropriate legal action against the attacker．
Many companies have blocked social networks as addicted employees can distract （分心）themselves on such sites，instead of focusing on work．In fact，studies show that British companies have lost billions of dollars per year in productivity because of social media addiction among employees．
Also，what you carelessly post on the Net can come back to trouble you．Leaking personal information on social sites can make users easily harmed to crimes like identity theft，stalking（尾隨犯罪），etc．Many companies perform a background check on the Web before hiring an employee．If a potential employee has posted something embarrassing on social media，it can greatly affect their chances of getting the job．The same holds true for our relationships too，as our loved ones and friends may get to know if we post something undesirable on social networks．
Social media has its advantages and drawbacks as each coin has two sides．It is up to each user to use social sites wisely to improve their professional and social life，and exercise caution to ensure they do not fall victim to online dangers．

（1）Paragraph 2 mainly shows that social networks

A

A

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A．benefit users in various ways
B．offer professionals good chances
C．guide users to make right choices
D．help students finish their homework
（2）Faced with problems caused by social media，some companies

D

D

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A．take legal action against the attackers
B．a(chǎn)void posting embarrassing information
C．refuse to hire potential addicted employees
D．forbid the use of social networks during work time
（3）The main purpose of this passage is to

A

A

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A．remind people to wisely use social media
B．provide some advice on social problems
C．raise public awareness of social problems
D．share experiences in using social media
（4）Which of the following shows the development of ideas in this passage？

B

B

I：Introduction
P ：Point
Sp ：Sub - point （次要點）
C ：Conclusion
A．
B．
C．
D．