[判断题]电缆沟的盖板开启后，应自然通风一段时间，方可下井工作。
A.正确
B.错误

{{B}} Social Networking{{/B}}
A large but long-in-the-tooth technology company hoping to become a bigger force in online advertising buys a small start-up in a sector that everybody agrees is the next big thing. A decade ago, this was Microsoft buying Hotmail--the firm that established web-based e-mail as a must-have service for internet users, and promised to drive up page views, and thus advertising inventory, on the software giant’s websites. This month it was AOL, a struggling web portal (入口网站) that is part of Time Warner, an old-media giant, buying Bebo, a small but up-and-coming online social network, for $ 850m.
Both deals, in their respective decades, illustrate a great paradox of the internet in that the premise underlying them is precisely half right and half wrong. The correct half is that a next big thing--web-mall then, social networking now--can indeed quickly become somethi