Ri: the fourth string is empty.

Mi: the fourth string and the second fret.

Fa: the fourth string and the third fret

So: the third string is empty.

La: the third string and the second fret

Xi: the second string is empty.

Extended data:

Common tuning methods of guitar;

With reference to calibration:

1, tuning with reference to the tuning fork: put a tuning fork in your ear and check the A sound of ① string 5.

2. Tune with reference to a special tuner: compare the empty string sounds of each string with the sounds on the blown tuner and adjust them to be the same.

3. Refer to the electronic tuner for tuning (as shown in the figure): use the microphone on the electronic tuner (connecting wire for electric guitar and electric box piano) to adjust the empty string sounds.

Overtone tuning:

The use of overtone tuning method should have certain ability to distinguish sounds and skills to play overtones. The sound we hear from an object due to vibration is not a simple sound, but a kind of "complex tone".

It consists of "pitch" (the sound produced by the whole vibration of the pronunciation body) and "double sound" (that is, "overtone"). Overtones are the sounds (natural overtones) produced by 1/2, 1/3, 1/4, and 1/5 of the pronunciation except the pitch. Because overtones are simple and easy to distinguish the pitch, it is more accurate to set the chord with overtones.