In music, 1 2 3 4 5 6 7,

The note names are C D E F G A B,

The roll call is do re ni fa sol la si.

The 61-key electronic keyboard*** has five groups of basic tone levels (that is, 1234567), which are called from low to high: large character group, small character group, small character group one, small character group two, and small character three. group plus four groups of small characters with only one key.

In addition, each number from 1 to 7, including white keys and black keys, is 12 keys. The 61-key electronic keyboard you mentioned has only one white key in the four groups, so the first five groups of 12 keys are multiplied by 5 groups = 60 keys, plus one key of the last four groups in small characters, it happens to be a 61-key electronic keyboard.

I am currently using a 61-key electronic keyboard.