1. Each measure contains a strong double beat and a triple beat, which are called single beats. Common single beats include: 2/4, 3/4, 2/8, 3/8, 2/2, 2/3, etc. Among them, 2/4, 3/4, and 3/8 are the most commonly used in music. .

2. A beat composed of single beats of the same type, with each section containing two or more downbeats, is called a compound beat. ? Common compound beats include: 6/4, 6/8, 9/8, 12/8, etc. Among them, 6/8 and 9/8 are the most commonly used in music.

3. Mixed beat, as the name suggests, is not a single beat, but a combination of different types of beats. The so-called different categories refer to beats with the same denominator but different numerators appearing in the same section. It's called a mixed beat. This kind of beat is a beat that alternates between equal numbers of strong and weak and unequal numbers of strong and weak in each measure, that is, the beat formed by the same unit beat, two beats and three beats added together, such as 2/4 3/4= 5/4 beat, then this 5/4 beat is a mixed beat.

Extended information:

Music theory mainly includes the pitch of the sound, the strength of the sound, the length and timbre of the sound.

1. Sound has four main properties: pitch, strength, length, and timbre. They are very important in musical performance, among which the pitch and length of the sound are the most important.

I don’t know if you have this experience: for a song, no matter whether you sing it with a human voice or play an instrument, whether the voice is small or loud, and no matter what key you use when singing or playing, the tone will be the same. The intensity and timbre have changed, but the melody of the song remains the same. However, if the pitch or length of the sound of the song changes, the experience of the music will be seriously affected. It can be seen that for a melody, the importance of pitch and sound length.

2. The pitch of the sound is determined by the number of vibrations (frequency) of the object in a certain period of time. The more vibrations, the higher the sound; the fewer vibrations, the lower the sound. The intensity of the sound is determined by the amplitude (the amplitude of the vibration of the sound waveform). The larger the amplitude, the stronger the sound; conversely, the smaller the amplitude, the weaker the sound.

The length of the sound depends on the duration of the sound. The longer the duration of the sound, the longer the sound; the shorter the duration of the sound, the shorter the sound. The timbre is determined by many factors such as the nature, shape and number of overtones of the pronunciation body.

3. Timbre refers to the sensory characteristics of sound. It is an important expression method in music that is extremely attractive and can directly touch the senses. The vibration of the sound body is composed of a variety of harmonics, including fundamental tones and overtones. The number of overtones and the relative intensity between overtones determine a specific timbre.

People’s ability to distinguish timbre is innate, and timbre is divided into vocal timbre and instrumental timbre. The timbres of human voices are high, medium and low, and are divided into male and female. The timbres of instrumental music are mainly divided into string instruments and wind instruments, and the timbres of various percussion instruments are also different.