天堂va蜜桃一区二区三区_网友自拍区视频精品_久久久在线视频_欧美日韩在线二区

曲譜簡介：

A lullaby, or cradle song, is a soothing song or piece of music, usually played for or sung to children. The purposes of lullabies vary. In some societies they are used to pass down cultural knowledge or tradition. In addition, lullabies are often used for the developing of communication skills, indication of emotional intent, maintenance of infants undivided attention, modulation of infants arousal, and regulation of behavior. Perhaps one of the most important uses of lullabies is as a sleep aid for infants. As a result, the music is often simple and repetitive. Lullabies can be found in many countries, and have existed since ancient times.