Because the service has grown so quickly, users are finding new uses of it.

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But their numbers have grown so quickly (see chart) that any plausible presidential candidate must court their support.

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Since then, the business has grown so quickly, and he has opened many branches and made it into a franchise business.

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Is it possible that China's local carmakers have grown so quickly that they have not developed the necessary depth of skills?

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Samsung has grown so quickly in the mobile phone market in the past year that its handset division has now become its most profitable business.

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It is hard to think of another job category that has grown so quickly and become such a force in society without having any tests, degrees, or regulation of virtually any kind.

WSJ: America's Newest Profession: Blogging – Mark Penn, WSJ.com

For one thing, it's grown so big, so quickly--it now has 16, 800 workers worldwide--that it's getting harder for employees to a make a mark.

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