即使在暴风雨期间，应急发电机也运行得完美无缺。

Even during the storm, the emergency generator ___functioned perfectly.

没有早上的咖啡，他觉得自己无法正常工作。

Without his morning coffee, he felt he couldn't ___function properly at work.

持续的零售销售对于任何经济的运行都至关重要。

It is important to have continuous retail sales for any economy to ___function.