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。
Mary is one of my classmate, who I admire very much. She is cheerful but friendly, keeping smiling at others. That impresses me most is her sweet voice. The sound of her singing is as a waterfall on a mountain, flowed effortlessly and leaving a sense of calm. She is very focused when singing. Much of us usually hear her to sing songs after class. She always active participates in local music contests. So far, she won two prizes in our city. She also teaches us to sing. As a result, influencing by her, more and more students in our class like to sing.
