Complex sentence: In the years before World War II, Mr. Sanabria formed and was the principal stockholder and president of American Television Corp., and set up and operated a very popular four year national correspondence school and a four year residence school in Chicago, Detroit and Los Angeles.
Split into simpler sentences: In the years before World War II, Mr. Sanabria formed and was the principal stockholder and president of American Television. They set up and operated a very popular four year national correspondence school and a four year residence school in Chicago, Detroit and Los Angeles.