Who knows Yu Yungang from Hohhot? Tell me about him!

I am a student of Hohhot Vocational and Technical School, and I am fortunate to have teacher Yu Wen teach me calligraphy. Mr. Yu Wen's title is full of enthusiasm. Believe me, he boasted more than calligraphy. In a 45-minute class, I boasted about my words for 20 minutes, and vomited that Ouyang Zhongshi made a fool of himself in a certain program. He also said that the words on the plaque in Hohhot were either written by him or by him, saying that he was 5000 yuan a word. Said a leader went to his house for questioning. Also said that this is not as good as him and which is not as good as him. Teacher Yu Wen is immortal!