~急急急！请帮我纠正一下语法错误、谢谢！！

There are countless things which are just like the stars in the sky happening during my study life these years.Although some of them i have forgotten with the time going,i will keep that thing happened a year ago in my mind forever.
I remember that the thing happened in the sports meeting,i represented my class to attend it ---the 200-meter-race."Peng!"the referee shot his gun and we ran at once.I tried my best to run but i could not run further after i ran 100 meters because i was so tied and i could not catch up with others at last. So i just got the forth which was the last one.
After the match, i was too sad to face the result.I was in my low spirits.A few while later i found that i should not have spend all my effort in the very beginning but i should have keep 20% of it for the last.
This little thing left me a very deep impression and now i find that i can not be that eager to be successful and spend all my effort at first.I should leave some behind.
这是我看了你的英汉文章后整理出来的翻译，从中我发现你的英文基本上都是直译的，这在英语学习上是不对的，你应该学会变通，想想你要表达的意思，然后换个比较好表达的句子写出来。

In my school life, there were many things happened. They are as countless as the stars in the sky. Some of them have been gradually forgotten, but there is only one thing still inside my mind.
That's something happened one year ago.
On the Sports Day , I represented my class to join the interclass game, the boy 200-meter dash. When the referee raised his gun and shot, I ran a hundred meters desperately. I was tired and had not enough energy. So I was lagged behind, and finally got the third runner-up (i.e. the bottom first). (Third runner-up 是第四名, 不是a fourth)
After the match, I dare not face such a result. My mood was terrible and I felt sad to death. After some psychological battles, I finally understood that I should not use all the energy at the beginning of the dash. I should save the 20% of the energy for the last minutes of the sprint.
It makes me unforgettable. We can't use all our energy for urging the immediate success. We have to save a part of it for the last.

only one thing makes me look so far difficult：这个应该用过去完成时，而不是一般现在时！
In my study life, there were many things, like stars, can even count. Some have been gradually forgotten, only one thing has made me look difficult so far!
That's happened a year ago thing.
That in the sports meeting, I have represented class attend grade game - man 200 meters dashWhen the referee raised his gun and slammed a ring, I desperately rushing, ran a hundred meters, tired, not enough energy, so being dumped behind, so get a fourth (bottom first name).
. After the match, I dare not face such the result of the match. The current mood of terrible, sad on top of the world. After some psychological battles, I finally understood the: sprint can't put all the physical with out to put twenty percent of the physical until the last sprint when used.
It made me unforgettable, can't eager to successful and put all the energy was exhausted, part of the left to the last.

坦白讲，最好是重新写一遍英语，因为里边基本全部是语法错误。不知道LZ是不是考虑好好再写一遍？或者我帮你写一篇了。。

你这根本不是英文，不要谈语法，语法没用，多看书，看人家怎么写的。你学中文你学过语法吗？