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There are many songs on Rain which i like and my favourites. but the few are :-
(1) Rim Jhim gira sawan \" - picturised on Amitabh and Maushmi for Manzil.
(2) Pyar hua igrar hua - Manna Dey and Lata - Shree 420 picturised on Raj Kapoor and Nargis.
(3) O\' sajna Barka Bahar Aayi - Parakh - Picturised on Sadhna by Lata Mangeshkar
(4) Rim Jim tarana lekhe ayai barsat - i do not the film , i think it is sung by Geeta Dutt and Rafi , picturised on i think Dev Anand and Waheeda Rehman but i am not sure but i like these songs. the other song i love is of mukesh sung for Shatrugan Sinha but i forgot the lyric, that too good. hence all these songs i like the most. on rain.