4. Line the flap up with the front of the mailbox, and cut another piece of tape to secure it in place along the bottom. Tape the second piece to the back of the mailbox. Tape it all the way around from the inside to form the back wall of the mailbox.
5. Cut two 6-inch pieces of ribbon. Tape one piece at the top of the inside of the mailbox flap, and tape the second piece inside the top of the mailbox. Tie the two pieces of ribbon together to keep the mailbox closed.
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