In piano scores, the bass symbol usually refers to a vertical line or a dotted line located at the bottom of the score, to the left of the keys, and is used to indicate the notes to be played by the left hand (bass range) of the piano. The purpose of these bass symbols is to help piano players better understand and master the rhythm and melody of the left hand. Below are several common bass symbols in piano scores and their meanings.

1. Left-hand clef (Bass Clef): The left-hand clef is located at the lower part of the music score and resembles a big ear with two points (picture). It is used to indicate the notes and melodies played by the left hand (bass range). In most pieces of music, the left-hand clef is fixed, instructing the player to use the left hand to play the notes in the lower register.

2. Octave Line: The Octave Line is a vertical line extending downward, used to distinguish a group of notes from the notes below and prompt the player to continue using the left hand Play notes in the lower register. When a bass vertical line appears in a piano score, it is usually marked with the word "LH" (Left Hand) underneath to help the player understand it better.

3. Octave Dash: The bass dotted line is similar to the bass vertical line. It is also used to distinguish a group of notes from the notes below and prompt the player to continue playing the bass area with the left hand. note. The difference is that the bass dash is a dashed line that extends downward, similar to other dashed lines in the score. In music, the bass line is also often referred to as "8va bassa" (an octave lower).

In general, the bass symbols in the piano score indicate the notes and melody to be played by the left hand. Using them can help the player better understand and master the rhythm and melody of the left hand part. In actual performance, the strength, speed, accuracy and other aspects of the left hand need to be coordinated with the right hand to play gorgeous piano music.