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。
Dear Tom,
How time flies! It’s been half a year since I become a senior high school student. In this period, I did quite good in my studies. Now I am one of the top student in my class. I wouldn’t have achieved so much with my teachers and classmates’ help. Mr .Wang, who teach math, is very patiently with us. With his help, I have made a great progress. And most my classmates are friendly. They always give me a hand when needed. However, I am grateful for their help. What is going on in my school? Tell me more in your next letter.
Yours,
Li Hua
