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。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。
As is well-known that birds are our friends. But the large number of birds have been killed for food. The other day I was walking in the woods while a shot was heard. Hearing the shot, the bird in the trees flew to all directions. A bird was injured badly and looked sadly. Finding the bird injured , so I decided to take it home . At home I take good care of it .When it recovered, I returned itself to the woods .I hope something should be done to prevent birds from killed .