Facebook is still very much a closed world of its own.

Facebook仍然是一个非常封闭的网络。

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McDonald’s has created its own closed supply chain, spanning beef, fries, bread and pickles.

麦当劳建立了自己封闭式的供应链，包括牛肉、薯条、面包和泡菜。

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Facebook has its own closed, internal E-mail system, for example.

例如，Facebook拥有封闭的内部邮件系统。

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With a closed looped of its own related products and services and marketing, AXP pricing has a built-in competitive advantage.

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To reinforce the purported similarity, the government has decided that each bank which is closed should have its own separate bridge bank, rather than have a single over-arching one.

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Outside the U.S., Amex has taken a step away from its closed loop model where it issues its own credit cards and also acts as the acquirer for merchants accepting the card.

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