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It was Sunday yesterday. Mike was at home with his mother. His mother said to him，"I'm going to the park. Are you going out?" "Yes, I am going to play basketball with Jack." Mike answered. "OK. Lock (锁) the door and take care of the key." said his mother. "I will." said Mike. His mother left. Mike finished his homework. He went to Jack's home. They played computer games together. Then they went to the playground. They played basketball. They had a lot of fun. It was almost noon. Mike wanted to go home. Mike looked for his key. He couldn't find it！His mother went back. She was angry," You forgot to lock the door!"