One day, a boy named Tim went to the beach with his mom. They saw the big surf and the water was very mysterious. Tim wanted to play in the water, but his mom said, "Be careful, Tim. The water is very mysterious today."
Tim played in the sand and built a big sand castle. He saw a small stick and used it to stir the wet sand. He made a moat around his castle. As he stirred the sand, he found a shiny key. Tim showed the key to his mom and said, "Look, Mom! I found a key in the sand!"
His mom smiled and said, "That's very interesting, Tim. Maybe it will open something special." They walked along the beach and found a small treasure chest. Tim used the key to open the chest, and inside, they found beautiful shells and shiny stones. Tim and his mom were very happy. They knew that the mysterious surf had brought them a special gift.
