Connection between 2 words

During the lesson the lecturer asked us to take 2 notes and write down
 2 words, give one note to the student sitting on the right and one note
 to the student sitting on the left and find a connection between the 2 
words.

The words I received are book and headphones, and then I thought to myself
 what I could write about a book and headphones and then I remembered.
When I read a book I listen to music with headphones and this is the context
 of the 2 words.