What are 5 key symbols and 5 key quotations from the book The Boy in the Striped Pajamas?

What are 5 key symbols and 5 key quotations from the book The Boy in the Striped Pajamas?

What are 5 key symbols and 5 key quotations from the book The Boy in the Striped Pajamas?

For symbols i thought of the fence, the window, the striped pajamas, their birthdays and the berlin house. But tell me what you think these represent?