Forty-three persons, including three from Evanston, became United States citizens on Dec. 16, taking the oath of allegiance in the Community Meeting Room of the Evanston Public Library. Officials from the U. S. Citizenship and Immigration Service presented the candidates and administered the Oath of Allegiance.  Congresswoman Jan Schakowsky, Mayor Elizabeth Tisdahl and Library Director Karen Danczak Lyons congratulated them and welcomed them to the country. Rep. Schakowsky urged each of them to register to vote. The ceremony at the Library was the culmination of a series of workshops to welcome new residents and teach them about the country and citizenship, said Ms. Lyons.