Original sentence: A failed shopping mall — which, ironically, was deliberately installed in place of the old city hall in a misconceived 1960s effort to revitalise the city centre — has now been converted into a federal office building, returning some hundreds of people into the core each day.As in other Canadian cities, the disappearance of Simpson's and Eaton's retail department stores, a proliferation of shopping malls and "big box stores" on, and a steady drift of entertainment venues to, the periphery of the city have damaged the vitality of the downtown core.However, in recent decades the central business district has suffered.Regina Downtown, the business improvement district for the area, is working to remedy planners' miscalculations of the recent past and return more people to work and to live and for special events such as the mid-winter Ice and Fire Festival
Edited sentence: As in other Canadian cities, the disappearance of Simpson's and Eaton's retail department stores, a proliferation of shopping malls and "big box stores" on, and a steady drift of entertainment venues to, the periphery of the city have shifted the vitality of the downtown core to other areas of this fine city.Citizens enjoy special events such as the mid-winter Ice and Fire Festival.However, in recent decades the central business district has been going through a period of change.Regina Downtown, the business improvement district for the area, is working to return more people to work and to live in this city.The old city hall in  city centre — has now been converted into a federal office building, returning some hundreds of people into the core each day