用所给词的正确形式填空。 1.Listen! Someone ______ (sing) in the music room. 2.Why ______ (do) they like running? 3.He ______ (not like) playing basketball. He ______ (like) playing tennis. 4.She sometimes ______ (go) to school on foot. 5.My hobby is skating. Is skating ______ (you) hobby? 6.I often help my mum ______ (clean) the windows on Sundays.