Musical numbers are frequent in Bollywood cinema, but rarely do the actors in the scene actually sing the songs. They merely mime, and a “playback singer” records a version of the vocal which is then layered over the top in editing.
The song’s namesake Asha Bhosle was one of the most prolific playback singers, with over 12,000 credited songs. Sadi Rani is another such movie singer.
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