Spanish last names are composed of two last names (one from your father and the second one from your mother; i.e. Gonzalez Perez). My immigration documents show both of them but there's an option to request for a different name to appear on certificate (3.b of the form). I intend to leave just one last name (Gonzalez) because Canadians use only one last name (the one that comes from your father). Is this a good move? Will this affect anything? What would it shown on my Canadian passport? Thanks in advance for your answers.