下文中共有10处错误，每句最多两处，错误涉及一个单词的增加、删除或修改。

下文中共有10处错误，每句最多两处，错误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：删除多余的词用斜线（）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. 每处错误及其修改仅限一词；2. 只允许修改10处，从11处起不计分。
Failure is part of our life. Somebody has ever achieved great success without lots of failures. One experience left lasting impression on me. I’ve been fond of playing the piano since my childhood. Last year there was a piano competition for teenager in my city and I take part in it. I couldn’t wait to show off. The day finally came. However, when I was on the stage I was very nervous that I made several mistakes while playing. My performance was a completely failure.
It was only after the competition when I realized my failure resulted in my lack of practice. From then on, I devoted more time to play the piano because I finally believe that practice make perfect.