The cave-making recipe calls for a steady emission of volcanic gas and heat, a heavy annual snowfall at an elevation high enough to keep it from melting during the summer.

洞穴的形成需要火山气体和热量的稳定释放，海拔高到足以防止每年的大量降雪在夏季融化。

youdao

In winter he had to wear a heavy coat and put his feet in a box to keep warm.

冬天，他不得不穿一件厚外套，把脚放在箱子里保暖。

youdao

Neither the green plants alone nor the heavy machines alone are sufficient to keep me alive.

不管是这些绿色植物，还是那些笨重的机器，单靠它们自己，都不足以保证我在这个空间的生存。

youdao

The weather is warm. They do not have to wear heavy clothes to keep warm.

VOA: special.2009.06.22

Tires themselves are also better at maintaining the kind of grip needed to keep heavy vehicles on the road during hard cornering.

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Even though I grew up on metal, punk and hard rock and the majority of my listening to this day takes place within those genres, I still keep a heavy dose of pop music in rotation.

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Even when talking heavy, keep it upbeat.

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