MOSCOW AND BOSTON — Lee Harvey Oswald’s Russian was still shaky in 1961, when he was working as a factory metalworker in the provincial Soviet city of Minsk. It fell to a young student engineer named Stanislav Shushkevich to help him out. "He was a simple martinet, and I found nothing in common with him. His Russian at that point was passable. We had about a dozen lessons in all, after that we had no contacts,” Mr.Shushkevich told the Monitor in an interview. “My main concern later on was that he would be given the task of fabricating equipment I...