1. A method for forming a duplicate image by reading an original image from an original sheet, comprising the steps of: designating a plurality of regions from a single original sheet by using region designating means; storing data representing each of said designated regions in designated region storage means; reading an overall original image from said single original sheet; forming a regional image located inside each of said regions on image carrying means; and assigning attribute data to each of said designated regions, said attribute data representing said designated region as an effective region; wherein N (N&gt;2) number of different regions are designated in said step of designating regions, (N-1)-th region is actively designated, a remaining N-th region is designated by failing to be positively designated or being actively designated; each of a plurality of said designated regions are stored in said designated region storage means along with identification number data for corresponding to the number of each of a plurality of said designated regions; and a regional image is selectively formed from said overall original image onto said image carrying means in accordance with said designated region data, said identification number data and said assigned attribute data.