Once upon a time, there was a boy named Tim. Tim loved to play outside with his ball. One day, he kicked his ball very hard and it flew far away. Tim felt sorry because he did not want to lose his ball.
Tim went to look for his ball. He saw a big tree and thought his ball might be there. He walked to the tree and saw a girl named Sara. Sara was kneeling by the tree, looking at something. Tim asked Sara if she saw his ball.
Sara said, "Yes, I found your ball. But first, let's look at this cool thing I found!" Tim and Sara looked at a big rock. On the rock, there was a word: "oxygen." They did not know what it meant, but they liked how it sounded. Tim and Sara laughed and played with the ball and the rock. They became good friends and always remembered the word "oxygen" as their special secret word.
