English: In very brief, it's a piano educational story of Czeny's 299 Works-collection book and one of its pieces - No. 27. I found it's treble part containing a whole view of a scale from high pitches to bass ones, which was suitable for a boy's nutrition of vocal situation - from higher pitches to his growth to be a man - bass part. Meanwhile, hands' controllability of 4 parts can also be improved. Therefore, in classroom, I suggested myself and my boy students to train themselves in usage of this piece. I thought it's good for them. I think: partly to say, appreciating Vienna school's beauties, meanwhile, training hands and notation-literacy, were the true purpose of Czeny's Etudes, rather than a piano-machine. Though compared with years' ago, several notes were out of tune- my singing... it's a whole view and I will modify it for better cultivation of piano students...