One possible version：

Dear Emma,

Thank you for sending me the photo of my family. I’m Peter Brown., a lovely boy. And I am 14 years old. There are six people in my family, my grandpa,grandma,my father,my mother, my sister and I .my father and my mother are teachers, and my sister and I are students, we are in the same class.

Peter Brown

题目分析：写作之前先注意审题，这一一篇描述性的文章，应用一般现在式和第一人称；写作时书写要工整，同时注意图画中人物不要遗漏。

【亮点说明】本文格式清晰，句子简单质朴，更点出爸爸妈妈的职业，同时说明了我和妹妹在同一个班级学习。文中使用了非常好的短语和句子为文章增色不少，例如Thank you for sending me the photo of my family；we are in the same class文章层次清晰，内容饱满，表达流畅。