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，每句中最多有两处。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：在错的词下划一横线，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。
Today I'd like to tell you something that I experience in the City Park. In the afternoon of last Sunday, my friend and I were taking a walk along a river in the City Park, when suddenly we heard a boy call for help in the river. We jumped into the river or pulled the boy out. Then we made him to breathe using the mouth－to－mouth way.Before the boy came to himself, we sent her to hospital at once and telephoned his parents.The boy was saved. His parents were very thankful us and the doctors thought high of our first aid. We realized that knowing first aid is very help and important because it can help you to save lives.