Hi again, I am trying to write good introduction as you said before.
It is one of my try out, hope you like it.

Do you agree or disagree with the following statement? Playing games is fun only when you win. Use specific reasons and examples to support your opinion.

Playing game is a part of a social life. We play games in every period of our life; when we are a child, when we are in a school and so forth.We sometimes play for fun, sometimes to earn money. If we do not play the game professionally I do not believe that playing game is fun only when we win. My arguments for this point are listed as follow.

This is a much better, stronger introduction, but you do need to really be careful with your use of grammar. Don't forget that when we use the Present simple to discuss general actions, any nouns that we use tend to be plural. I have rewritten your introduction with corrections. I have also taken out the "and so forth" has it really has no place in this sentence.

Playing games is a big part of our social life and we play them throughout most of our lifes such as when we are children and when we are at school. Sometimes, we play for fun, and sometimes for money. If we do not play games professionally, I do not believe that playing games is fun only when we win. My arguments for these points are as follows.

I will post some advice on writing an introduction later today, so keep an eye out.