Suddenly, the sky becomes dark. I look up and see dark storm clouds.

突然，天空变黑了，我抬头看到黑色的乌云。

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Dark storm clouds and the threat of lightening are keeping space shuttle Discovery on the ground.

NPR: NASA Sets New Discovery Launch Date for July 4

Dark storm clouds appear to be looming for Google in China.

FORBES: Google In China: It Doesn't Look Good

It means strengthening power systems with smarter designs to prevent the multi-day outages that left hundreds of thousands in the cold and dark for days following the storm.

FORBES: Rebuilding In A Warming World