Complex sentence: The Metro Gold Line is a light-rail line that passes through Union Station between Pasadena and East Los Angeles using Tracks 1 and 2 of Union Station's 14 outdoor tracks.
Split into simpler sentences: The Metro Gold Line is a light-rail line that passes through Union Station as it travels between Pasadena and East Los Angeles. Trains use Tracks 1 and 2 of Union Station's 14 outdoor tracks.