You can't completely pigeonhole Skype when it serves both as a partial substitute for traditional phone service and an instant messaging service with voice and video on top.

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Self-service is no substitute for savvy hiring.

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He questioned whether the ECPs would simply be a "substitute rather than a supplement" to the existing service.

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Craig Raeburn of TyMetrix, a provider of Web-based management solutions for corporate law departments, correctly acknowledges that technology is not a substitute for the knowledge, intuition, and skill of lawyers and other legal service professionals.

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And normal service was quickly resumed when Van Bronckorst again supplied the inviting cross, substitute Bergkamp this time providing the easy finish.

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Military service had a neutral effect on socioeconomic attainment, and therefore did not substitute for additional formal education among these veteran enlisted men.

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