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Yesterday Sun Yu wanted to go to the park with her friends. She wore a yellow T-shirt. Her brother Sun Yang saw her and said, "Don't wear my T-shirt." "No! It's my T-shirt," said Sun Yu. Their sister Sun Li came. She said, "Don't argue! This is my new T-shirt! Look! Your T-shirts are on the line. I washed them for you yesterday." "Oh, I'm sorry! Thank you," they said together.