What could I shoot for a book?

I'm doing a photography assignment for school, where I shoot a lot of photos to make into a book. I originally chose emotions but my teacher said it was too hard and told me to change it afterwards. Now, I'm a little unsure of what my topic should be about as I have nothing to use that my peers aren't using. I was thinking of something abstract but it's really hard to think of sm. Could you pls help me?