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。

    Hello, boys and girls! Today, I am going to talk with what you should do when a fire alarm go off. If you hear the alarm, stand in line at the door and wait your teacher to lead you outside. Stay close to your teacher and classmate. Don't panic or get out of line, and trying to remain quiet and calmly. Soon the firefighters will come and put out a fire. If it's a false alarm and there is no fire, your teacher will lead us back to the classroom. If you notice that when someone is missing and hurt, tell your teacher immediately.