用所给词的正确形式填空。
Today is my _________(sister)birthday. My mum _________(buy)things at the supermarket. My dad _________ (clean) the room. My aunt can _________ (make) birthday cakes. She _________(make) a big birthday cake. My brother can _________ ( draw ) pictures. He is making a birthday card. I _________(play) the piano. My sister _________(sing). We are happy.