They are as follows:

1. Accelerately: accelerando (English [?k?sel?r?nd?]? American [?k?sel?r?ndo?]? ), abbreviation accel.

2. Acceleration: ritardando (English [?ri: tɑ: 'd?nd?]? US [?ri: tɑ: 'd?ndo?]), abbreviation rit .?

3. Crescendo: crescendo (English [krend?] American [krendo?]?), abbreviated as cresc

4. Decrease: diminuendo (English [d?m ?nju?end?]? US [d?m?nju?endo?]), abbreviated as dim.

Speed ??terms include basic speed and changing speed. Crescendo, crescendo, crescendo, and decrescendo are changes in speed. Contrary to the basic speed terms, they refer to temporary changes in speed during playing.

Mastering the inherent relaxation of speed included in the terminology of speed is very beneficial to the performance of the music, especially the connection of phrases and the performance of the ending part of the phrase.

Extended information:

The basic tempo in music usually indicates the unified tempo of the entire piece of music or a section.

Basic speed terms can be classified into three types according to their origins:

Type 1: terms that appeared in the early days and were specially used to record speed, and are still used today, such as Presto (Presto), Lento (Adagio), etc.

Category 2: Evolved from expression terms: For example, the word Allegro, which comes from Italian daily life terms, has meanings such as happiness and joy, and gradually evolved into a musical term - Allegro.

Category three: Use the names of well-known genres to indicate the speed: such as Tempodimarcia (march speed); Tempodivalse (waltz speed).

Both the basic tempo terminology and the metronome label M.M. can mark the basic tempo of a piece of music. The term mark only indicates the speed level, and the term mark has a certain expressive meaning.