Mary S.Thomas;84;formerly of Fayette Avenue;Belle Vernon;died Wednesday;July 7;1993;in Westmoreland Hospital;Greensburg;following a lengthy illness. Mrs.Thomas was born Dec.28;1908;in Mays Landing;N.J.;a daughter of the late Harry and Bertha Risley Stanger. She had been an elementary teacher for many years in the Belle Vernon school system and had also been a substitute teacher for many years. Mrs.Thomas had been a resident of Belle Vernon for many years. An avid bridge player;she belonged to numerous bridge clubs over the years. Mrs.Thomas was a member of the First United Methodist Church of Belle Vernon and the Mimiriam Literary Society. Surviving are one son;Richard Thomas;formerly of Belle Vernon;three sisters;Evelyn Aspy of Clarksburg;W.Va.;Gertrude Spicci of Hartford;Conn.;and Emma Anderson of Queens;N.Y. Her husband;Evan W.Thomas;died in 1982. One sister;Mildred Smith;and two brothers;Russell and Wilber Stanger;are also deceased. Friends will be received Thursday from 2 to 4 and 7 to 9 p.m. in the Rhome Funeral Home Inc.;1209 Grand Blvd.;Monessen. Services will be held Friday at 11 a.m. in the chapel of the funeral home with the Rev.Dr.Thomas St.Clair;pastor;First United Methodist Church;Belle Vernon;officiating. Burial will be in Belle Vernon Cemetery. The Rhome Funeral Home Inc.is handling arrangements.