There are no readings of 8 and 9 in music. The readings of other numbers are as follows:

1 do, 2 re, 3 mi, 4 fa, 5 so, 6 la, 7 xi

Extended information:

Simplified notation: This is a simple notation in music, with 7 basic sound levels. Simplified musical notation refers to a simple notation method. There are two types of alphabetical notation and number notation. It originated in France in the 18th century, and was later improved by the Germans and became what it is today.

The commonly referred to as simplified musical notation refers to digital musical notation. The digital musical notation is based on the movable solfa method, using 1, 2, 3, 4, 5, 6, and 7 to represent the seven basic levels of the scale, which are pronounced as do, re, mi, fa, so, la, and si. Rest is represented by O. The duration name of each number is equivalent to the quarter note of the staff.

Reference: Baidu Encyclopedia Music Score