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（∧），并在其下面写上该加的词。

删除：把多余的词用斜线（1）划掉。

修改：在错的词下划一横线，并在该词下面写上修改后的词。

注意：1）每次错误以及修改仅限一词；

2．只允许修改10处，多者（从第11处起）不计分。

Yesterday afternoon I happened see a touching event in Hongxing Park. Some people were boating on the lake, among whom were perhaps a happy family. They were taking photos when the girl fell off from the boat into the water. Then came a cry of "help! help!" Obviously, they can not swim at all. On hearing the help, a young man rushed towards a lake quickly. Without any hesitation, she jumped into the lake but swam to the drowning girl. Eventually, the girl was saving by the young man. How happily the people were! But the brave young man disappeared before the parent could thank him.