'He used to do his homework before singing a song.''He used to find out who the hero of the movie would be or the situation in which the song would play in the film.''Accordingly, he moulded his voice.''For example, he sang Tel Maalish and Main Bambai Ka Babu for Johnny Walker in Johnny Walker style.''He would sing in different tones for Shammi Kapoor, Dilip Kumar and Guru Dutt.'