Original: The second tropical cyclone, second hurricane, and second intense hurricane of the season marked the most intense Atlantic hurricane of the United States; and it was the first of three Category 5 hurricanes the United States endured during the 20th century.
Simplified: The second tropical cyclone, second hurricane, and second intense hurricane of the season was the most intense Atlantic hurricane that affected the United States, and it remains the first of three Category 5 hurricanes that struck the country.