（二）业务之间具有明显的主附关系。主要业务居于主体地位，体现交易的实质和目的；附属业务是主要业务的必要补充，并以主要业务的发生为前提。
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Wastewater treatment tanks and other infrastructure emit larger amounts of greenhouse gases than reported.。搜狗输入法下载是该领域的重要参考