Elena jogged (慢跑) with her dad in some empty lots (小块地). These out-of-the-way lots were good places to jog. But the lots were full of rocks and rubbish.
    One day, Elena saw a sign on the lots. It said, “New City Park”. Elena was excited. Maybe the park would have a jogging trail (路径)! Elena told her parents about the sign.
   “I read about the park in the newspaper,” said Elena's father. “The city wants volunteers to help clean the area. Then the city will build a soccer field and a playground. But the paper didn't mention a jogging trail.”
“Well, perhaps if I help clean up the lots, they'll put in a jogging trail,” said Elena.
    On Saturday Elena went to the lots. Many adults were working there. Some were picking up rubbish. Some were moving rocks. Elena looked around. She could carry rubbish, and she could move rocks. So she went to the area every week to do volunteer work. She told everyone she was glad to help build the park. She explained that she hoped the park would have a jogging trail. Then everyone knew her and her jogging trail.
Soon the volunteers cleared the lots. The city could start building. The mayor (市长) gave a speech. He showed a drawing of the new park. He told them about the soccer field. There would be picnic tables. There would be a playground. The park would even have basketball courts. But there was no sign of a jogging trail.
    The mayor thanked the volunteers. Then he asked if they had any suggestions. The volunteers said they wanted to build a jogging trail around the park. They told the mayor how helpful Elena had been and how she wanted a jogging trail. The mayor then said, “A jogging trail won't be hard to build. Let's do it!”
    Everyone clapped and cheered.

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