The traditional lavalier/neck-hanging microphone which teachers use easily generates noises and sharp sound, making our ears eventually fatigued. To enhance the sound quality and avoid the noise, using wired microphone can be a better way. However, we should be careful with being stumbled by the wire, which limits our moving flexibility. The wired microphone is also much heavier that may damage our hand joints for long-term. That’s why we can see many teachers have the occupational disease.