Complex sentence: The yacht "Granma" arrived in Cuba on December 2 1956, carrying the Castro brothers and 80 others, even though the yacht was only designed to accommodate 12 people with a maxiumum of 25.
Split into simpler sentences: The yacht "Granma" arrived in Cuba on December, 2,1956, carrying the Castro brothers and 80 others. Although it the yacht was only designed to accommodate 12 people with a maxiumum of 25.