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处错误，每句中最多有两处。错误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：在错的词下画一横线，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 Mr. Black,
I’m very thank to you for inviting me to stay with you in the come summer vacation. I have been dreamed of seeing you again so that I can get help from you in my English learning. And I’m afraid I cannot go to your place in this summer. I’ve promised my grandmother, she lives in the country, to spend this summer with her. She misses me too much that I find difficult to refuse her request. I’m busy preparing for my examinations in present. I planned to visit you in winter if it’s convenient to you.
Best wishes.
Yours truly,
Li Ying