Complex sentence: It's celebrated with singing, dancing, drinking and general merriment on the 13 April every year.First day of Biju is called "phul Biju", second day is called mur Biju.
Split into simpler sentences: It's celebrated with singing, dancing, drinking and general merriment on the thirteenth of April every year. The first day of Biju is called "phul Biju," and the second day is called mur Biju.