Student use of computers

We can see (observe) that the average number of hours a student spends on the computer per a week has increased by less than two hours between 1995 to 2000, then to 14 hours in 2005. (do you mean it increased by 14 hours between 2000-2005, or that in this period students spent 14 hours total on the computer? not clear)  
What is the reason for this phenomenon ? Firstly, with the development of society (in your example, it is technology that developed, not society.) technology. Computers have more and more functions that can be used for our work and life. So make it's possible to communicate with people face to face in most parts of the world by computer. Secondly, the price become cheaper and cheaper (太中文想法）has dropped exponentially —most university students can afford one.
Voice for and against computer have been heard since their birth (sorry, this is really confusing to a native speaker!) Since the advent of computers, there have been both advocates and critics. Some people believe that students who spend all their time playing video games will abandon their studies. Meanwhile, the cost of repairing computers is too great, and it is also very time-consuming.
I believe we should treat this phenomenon the right way and make good use of the advantages of computers and eliminate the disadvantages.

About recycling*- government should make it compulsory

Our world is surrounded by trash now. Statistics show that many cities, especially the big ones, are full of rubbish which were mainly comes from homes. Based on this issue, there are many people say that it is the governments who didn't well accomplish their abilities, they say that there are still plenty of domestic waste need to be recycled.*

(this is very confusingly written: you say "based on this issue," and then you make a claim about the government, even though the preceding sentence does not mention the government. You should add something that makes the connection between these two ideas clear.)

Because of this, there are many people who say that it is the governments who haven't done their job; they say that there is still plenty of domestic waste that needs to be recycled.

Recycling* is an important and difficult issue for most of the countries. Many kinds of waste can't decompose naturally. For example, the plastic trash cannot decompose naturally*, and unless we recycle and make a good use of them, or they will either end up piled up on the ground or buried in the earth. (*太中文方式想法。用英文时，必须说：“比如，名词+动词”） Governments do have a responsibility to take care of this, I think it would be good to let the government make it a policy or a legal law.
However, the citizens also need to take the responsibility to recycle because it is a huge undertaking which need to be done by each member of the society. What's more, conscientiousness is far more important than laws.
In conclusion, (this is a very clichéd way of ending an essay that nobody likes reading; avoid in the future) both laws and citizens' participants are important for increasing recycling compliance. With the effort from both sides, I think this issue could be easily resolved.

A small city which locates Beijing nearby

My town is close to Beijing nearby. It is a small city: there are only 4.5 million people in it. Maybe that figure is large compared to some other countries' cities, but compared to Beijing it is small. Nevertheless, you cannot look down on it (正确的，然而更自然的是：But don't underestimate it), because its location is very favourable. It is located between Beijng and Tianjin, and is called the Gallery Of JingJin (?). It's only less than an hour's drive from Beijing or Tianjin. In fact, there are (从来不写下there're) a lot of people who commute from here to the capital every day. But, for every advantage, there is a disadvantage. Its favourable geographical location drew too many people here, which made the price of real estate rise day by day (更自然的：the price of real estate has risen exponentially). Frankly, it was just a third-tier city, even was not even a well-known city in its own province. I hardly know of any historical episodes that happened here except that of the “Great Victory”. Its consumption level is as high as Beijing's, and almost exceeds that of most provincial capital cities. I think this is a bit of a sick situation. But anyway, we must accept the truth. Indeed ,there's no way to escape.

关注标点符号用法！

*「every advantage has its disadvantage」 的意思就是，每个好处不是完全的好处，有什么缺点。我猜你企图说，每个优点有对方的缺点

Toothache pain

As the proverb says: A toothache is not a big deal, but the pain is very real. A few days before I got a toothache, I preemptively took some painkillers.After hurting for several days, I finally went to a dentist finally.

A Diary, Mar,4,2107

I was nervous when I realized I have a meeting tomorrow morning, and have to show my work that I have done this week to my teacher. The reason is that I haven't gotten any work done. So I spent all my time today to doing something.
The second thing I want to note is that I hit on my counselor*. At the beginning, I said I missed her. She replied to ask me why I didn't visit her. So I responded that I was planned to see her at the winter vacation, but I had been studying English so hard that I forgot my plan. Then I asked her about her address. She asked me what are my English level was. I said it's so low that I failed the CET-6 but I am determined to score 600 points at the next CET-6.

* "hit on" 就是 “挑逗“。你是不是说 ”打电话“(=to call)？

One reason is that the relationship was not strong enough to be tested. (as a point about essay writing, this is a confusing claim because you are saying, "The reason the relationship did not last is because it was not strong enough to last," which is not a "reason." Instead say: The relationship was not strong enough to last. I once had a friend of mine who could talk about anything and everything before. When we were in a bad mood, we would always listen to each other, and then give each other consolation and blame somebody for our problems. When we got together,  we would mostly gossip. I had always thought we were closely linked and inseparable because we knew each other too well. However after we had a fight, we went our separate ways. So far I can’t understand that we are just quarreling why she had to spread rumors everywhere and even fabricate untouchable (? 你的意思不清楚) gossip to slander me. I have never told her secrets to anyone. She knew me so well that she knew what would really hurt me. I didn’t accept her apology, because I cannot trust her ever again. Our friendship is like shorn hair that can't be reattached. Since then it has not been easy for me to believe anybody.