Today,rollerskating(滑旱*)iseasyandfun.Butmanyyearsago,it...
问题详情：Today,rollerskating(滑旱*)iseasyandfun.Butmanyyearsago,itwasn’teasyatall.Before1750,peoplenevertriedskatingonwheels.ThatchangedbecauseofamannamedJosephMerlin.Merlin’sworkwasmakinginstruments...