The " ventriloquism " was a traditional musical instrument playing technique in ancient China, also known as " blowing ventriloquism "," blowpipe ventriloquism ", or " whistling ventriloquism ". It refers to the way the air forms different sound effects in the mouth of the pipe by whistling or blowing the bamboo pipe. This kind of playing technique was often used in ancient China to play flute, xiao, harp and other musical instruments. It could also be used to express some artistic conception and atmosphere.