The solution turned out to be advertising, and it's not an exaggeration to say that Google is now essentially an advertising company, given that that's the source of nearly all its revenue.

最终的解决方案是做广告；并且毫不夸张地说，谷歌现在本质上是一家广告公司，因为这几乎是它所有收入的来源。

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There's no mystery as to the source of all the trouble: advertising revenue has dried up.

要问所有这些麻烦的源头，答案并不神秘：广告收入已经枯竭。

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It sees online advertising as an unreliable source of revenue.

它把在线广告视为不可靠的收益来源。

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But to hear Mr. Schmidt tell it, the real challenge is one not yet on most investors' minds: how to preserve Google's franchise in Web advertising, the source of almost all its profits, when "search" is outmoded.

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Its housing guide is a good source of advertising revenue since housing management companies generally have regular cash flow.

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But Facebook dismissed the decline noting that its biggest revenue source, advertising, typically slows down in the first quarter.

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