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。   

    I was used to feel sleepy in class and couldn't focus on the lessons the teachers give. As a result, not only did I do bad in my studies, but also my health went from bad to worse, about which I was often scolded by my parents. I was also worried my situation. About half a year ago, followed the head teacher's advice, I began to take part in some sport activities. I had kept on playing basketball for 45 minutes and so every day till today. Now my health has been greatly improved, so at the same time, I've made good progress in all my lessons. Physical exercise has changed me into an entire new person!