This linking together in turn lets us tap our cognitive surplus, the trillion hours a year of free time the educated population of the planet has to spend doing things they care about.
From the transfer of the specific model, the U.S. transfer of rural surplus labor migration patterns are free.
从转移的具体模式来看，美国农村剩余劳动力的转移属于自由迁移模式。
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During the execution of the Works, the Contractor shall keep the Site free from all unnecessary obstruction, and shall store or dispose of any Contractor's Equipment or surplus materials.