What kind of postcard is it for Mr. Sun?

Poetry. In Postcard for Mr. Sun, Grandma Ju wrote a postcard to Mr. Sun, expressing her gratitude and greetings to Mr. Sun, and also teaching people the value of life and the importance of cherishing time. Poetry is a lyrical literary genre, which vividly expresses the author's rich feelings in highly concise language and is a rhythmic literary genre.