The position of each sound in the harmonica is fixed. The key to finding the sound is to find it by hand on the basis of knowing the position of each sound. Don't move your head and mouth to find the sound, it's hard to hear, and you can't find the sound to play quickly. At first, the 24 tones of the harmonica will look dazzling. You can play alto first, arrange it regularly, and then gradually expand the range to bass and treble, so you won't find it difficult to learn. It seems difficult for us to find the sound by observing the harmonica. In fact, practice makes perfect, which I think is its advantage, so that we can concentrate on reading music and learn more conveniently.
The 24-hole polyphonic harmonica has no rising or falling tone, which is equivalent to only the white keys of the piano and no black keys. The sound of Sky City is changing, and black keys is needed, so you can't do it with a polyphonic harmonica. Just jump with a C harmonica. The most suitable polyphonic harmonica for tone sandhi is the national patent semitone series harmonica, which can easily play music in any key. I hope it helps you.