I am also a teacher, and I have two calligraphy works at home: The Book of Commandments and The Book of Dwelling House. I think the most inappropriate words are that peaches and plums are everywhere, teaching and educating people ... These words are all praise for teachers. It's like you gave an official an innocent photo. You said this official would not hang up. If he were an honest official, he wouldn't hang up. If it is a corrupt official, he is embarrassed to hang up. So it is better to choose your favorite ancient Chinese or idioms.
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