LinkedIn to enhance their career and business development. Students can work together wit h 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 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 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. Revealing（泄露） personal information on social sites can make users vulnerable（易受伤害的）to crimes like identity theft, stalking, 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 enhance their professional and social life, and exercise caution to ensure they do not fall victim to online dangers.

28. Paragraph 2 mainly shows that social networks _________.

A. benefit users in various ways

B. offer offer professionals good chances

C. guide users to make right choices users to make right choices

D. help students finish their homework

29. Faced with problems caused by social media, some companies ________.

A. take legal action against the attackers

B. avoid posting embarrassing information

C. refuse to hire potential addicted employees