When the needle enters the red zone the engine is too hot.

当指针进入红色区域时，发动机就过热了。

《牛津词典》

Their dusty compound at the edge of town is filled with secondhand models from Japan, including saloons, off-roaders and a bright red fire engine.

他们那个布满灰尘的院子在小镇边上，堆满了来自日本的二手车，其中有轿车，越野车和一辆鲜红色的消防车。

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The stoplight in front of the Musas' car turned green, then red, and then green again, but the car remained in place, the engine still rumbling.

穆萨车前方的交通灯变绿，又变红，再变绿，车却丝毫未动，引擎还在隆隆作响。

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Rihanna walked the red carpet in a fire engine red gown with sheer detailing on the midriff from Alaia.

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And just in case you've forgotten that you're in China, the chocolate boutique features small linen squares lacquered a fire-engine red.

WSJ: Stays: Conrad Beijing

It's probably mostly its tiny size -- and the fire engine red probably doesn't help its case much in that respect, either.

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