Complex sentence: When Parker and Stone made fun of celebrities in previous "South Park" episodes, they were chosen at random; however, they chose to mock Barbra Streisand based on a strong distaste for the actress.
Split into simpler sentences: When Parker and Stone made fun of celebrities in previous "South Park" episodes, they were chosen at random. However, they chose to mock Barbra Streisand based on a strong distaste for the actress.