They sing when they are out on the prairies, when they welcome guests, when they have parties; they sing to express emotions both merry and melancholy. None of the lyrics or melodies have a particular standard; the rule is to let loose one's feelings.
在草原上唱，迎賓、宴客也唱，歡樂與悲傷都是用歌唱來表達情緒，歌詞、曲調也一無標準，反正就是讓感情奔放出來就是。