假定英语课上老师要求同桌之间交换修改作文，请你修改你同桌写的以下作文。文中共有10处语言错误。每处错误仅涉及一个单词的增加、删除或修改。
增加：在缺词处加一个漏字符号（^），并在其下面写出该加的词。
删除：把多余的词用斜线（\）划掉。
修改：在错的词下画一横线，并在该词下面写出修改后的词。
注意：（1）.每处错误及其修改均仅限一词；
（2）只允许修改10处，多者（从第11处起）不计分。
   When I was in the four grade，I joined in a piano competition.I spent four hours practising playing the piano every day.Mine piano teacher came three times a week help me.A few weeks later，I made much progresses.Then the big day finally arrived.I was so nervous when they called my name.I went up and start to play.While I was show the music，everyone sat still and listened.The song was play without any mistakes.Then I waited for them to call out the winner.When I heard from my name，my heart was beating so quick that I thought I would stop breathing.I couldn't believe it.I won!It was the happy day of my life!