Complex sentence: Anjaana Anjaani is the story of Kiara (Priyanka Chopra), based in San Francisco, while Aakash (Ranbir Kapoor) is a New York City boy.
Split into simpler sentences: Anjaana Anjaani is the story of Kiara (Priyanka Chopra), and Aakash ((Ranbir Kapoor)). Kiara is based in San Francisco, while Aakash is a New York City boy.