Single is simple, double is trouble.

一个人很简单，两个人很麻烦。

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"The clear message is that breast cancer is not a single, or a simple, story, " Friese said.

CNN: Breast cancer awareness: Not so pretty pink

To further simplify movie shooting, Live View is activated at a single flick of a dedicated switch, and HD video recording is achieved by a simple press of a button.

ENGADGET: Nikon D3100 gets real, adds 1080p movie mode with continuous autofocus

The United States is made up of single-member districts where a simple majority wins a congressional seat and the loser gets nothing.

ECONOMIST: Europe's treaty conundrum