Irrfan Khan has proved his mettle with serious acting as well as showing his humorous side with ‘Piku’. However, the Bollywood actor has always refrained from dancing and singing in career spanning almost 18 years. Irrfan explains, “When I go on singing shows, I feel why I didn’t practice that. During my drama days in school, we used to have singing classes. But we always used to bunk them. Today I regret that.” Irrfan will soon be seen in ‘Madaari’, which he is also producing. The film is a social thriller and hits the screens on July 15.