How to play the notes b, a, and g on a recorderHillary Hill demonstrates to us how to play a mouth piece. Note b is played by completely covering the thumb hole in the back and the thumb hole in the front. Remember to cover the hole completely to avoid squicky sounds. Note a is played by covering the thumb hole in the back, the first hole at the top and the second hole. To play g, its the thumb hole and the top three holes on the piece. Its important to use the left hand because when we learn more notes we use the left hand for the top holes the and the right hand for the bottom holes.