Complex sentence: The next year, Horton sang at Vauxhall Gardens, and in 1830, she appeared at Covent Garden Theatre as Mealey Mouth in "Harlequin, Pat, and Bat".
Split into simpler sentences: The next year, Horton sang at Vauxhall Gardens. In 1830, she appeared at Covent Garden Theatre as Mealey Mouth in "Harlequin, Pat, and Bat".