What does your monther often do on weekend?mary goes skateboarding（once a week）（对括号类部分提问）How often does Mary go skateboarding .lucy always surfs the internet（改为否定句）Lucy doesn't always surf the internetThe old man exercises every day（改为一般疑问句）Does the old man exercise every day?（温馨提示：你的追问已够三次，再追问会被系统扣分的）