文中共有10处语言错误，错误涉及一个单词的增加、删除或修改。
增加：在此处加一个漏字符号(∧)，并在其下面写出修改的词。
删除：把多余的词用斜线(＼)划掉。
修改：在错的词下划一横线，并在其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（从十一处起）不计分。
Dear sir,
I'm glad to recommend (推荐) my friend Li Ming to you. Li Ming was born in July 15, 1974 in Beijing. He graduated from Xisi Primary School in 1986 .When he was in the middle school, he did good in maths, physics and chemistry and fond of art. After graduating from No. 4 High School, he entered Beijing University study physics. After four year of hard work there, he went to the United States for further study. Because of his excellent work, he get a doctor's degree in physics in last year. He is now in good health but would like to make contributions to our country．I will be most gratefully if you consider my recommendation．
Looking forward to receive your early reply!
Yours truly,
Wang Lin
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=
，则x=y