题目内容：

    In today's world, online social media has become more powerful and the most destructive thing over worldwide , although with time all generations have come to accept the changes social network has brought about, teenagers and young adults are the most enthusiastic users of these sites. According to various research studies in the field of online social networks, it has been revealed that these sites are impacting the lives of the youth greatly. When using these sites such as Twitter, Facebook or Myspace, there are both positive and negative effects on the youth.

Firstly, social media helps the youth and any other user updated with what is happening around the world, and helps the teenagers stay connected and interact with each other even if they are many miles apart. This strengthens their relationship. Even if they finished school and moved to different locations, they stay connected and update one another.

In addition, social media sites have provided a platform whereby the youth can create groups and pages based on their common discipline and end up building connections and opportunities for their respective careers by updating different topics to discuss. Youth who have been interviewed say that social media has become their lifestyle and it makes their lives easier and more efficient.

While on the one hand social network sites seem to bring people together and stay connected, on the other hand it causes many physical and mental health problems such as eyes infection, back problems, etc. Other negative effects of social networking various people suggested included encouraging poor spelling and grammar , exposing underage to online predators （捕食者）,allowing spread of misinformation that is seen as fact, decreasing productivity as those who are supposed to be working spend time in the sites to chat, providing a perfect platform for cyberbullying and providing details that increase risks of identity theft.

"The more social media we have, the more we think were connecting, yet we are really disconnecting from each other. " One researcher said.

In conclusion, social networking clearly portrays both positive and negative effects on the youth. It is the decision of individuals whether to use it in a right way or wrong.

1.Why do young people adopt the platform offered by social media sites?

A.To practice their debate skills.

B.To change their way of living.

C.To improve their academic performance.

D.To lay the foundation for their future careers.

2.It can be inferred that the main disadvantages of social networking may _______.

A.put young people in danger

B.allow spread of information

C.let out users' health problems

D.reduce the using of poor spelling

3.What is the passage mainly about?

A.The research on online social media.

B.The correct way to use online social media.

C.The introduction of online social media history.

D.The influence of online social media on the youth.

4.What is the authors attitude towards social media?

A.Disapproving. B.Objective.

C.Positive. D.Indifferent.