While outside developers have long created mini-applications that complement the offerings of the two social networks, they've often had an ambivalent relationship with their hosts.

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We can do it if we know how to make the most of how our two economies complement each other.

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Regional operators are teaming up with private equity firms to place bids on one or two of the clusters that would complement their own businesses.

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The two really complement each other, and the use of photography in graphic novels is something I think we're going to see more of.

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Instead of one satellite carrying every instrument, EPS-SG is likely to split the complement across two separate platforms.

BBC: Weather satellites and the gathering storm

While those two substances complement each other, Jarmusch, ever the hip mad scientist, throws together odd combinations of actors and singers.

NEWYORKER: Coffee and Cigarettes