love is one of the main themes because even after she was killed by the Angels he would sleep in her tomb believing that their souls were intertwined and that their love for each other would never die.
why death was the other main theme was because Angels were so jealous of their love for each other they killed annabel by wind of a cloud. and even after death her true love would still sleep with her in the Tomb
It just means that you have to choose one quote, write about a book you've read from that perspective and talk about how it applies to something else you've read. Use details from that book. When I have a question like this I usually just ask my teacher because they know best. Ask your teacher(email because they are always there to help).