Just as peer-to-peer businesses like eBay allow anyone to become a retailer, sharing sites let individuals act as an ad hoc ( 临时的) taxi service, car-hire firm or boutique hotel (精品酒店) as and when it suits them.
出自-2013年12月阅读原文
Next, consider eBay, Having started out as a peer-to-peer marketplace, it is now dominated by professional "power sellers" ( many of whom started out as ordinary eBay users)