Assaulted in her own home

Description: A large hand over Mary's mouth prevented any sounds from coming from her, while a strong arm around her body held her in a firm grip.Soon she was bound in a hogtied with a tape gag over her mouth. She could hear the burglar searching her apartment for jewels, and suddenly he was standing in front of her "There, I'm done here. Have fun!" he said and shortly after Mary heard the front door close. She herself tried everything to get free from the ropes, but they were too tightly tied. How was she supposed to get free?