We need a spare engine for this sled.

我们需要为这个雪橇准备一个备用发动机。

youdao

Spare engine: We will provide at least one spare engine ready in China for each aircraft.

备用发动机：我们能为每架飞机在中国至少提供一台备用发动机。

youdao

I can't spare a week, so instead, I help him unload fish from the hold of the Lauren Dorothy, a friend's boat, while music blares over the noise of the engine.

我一周也抽不出时间，只好帮他把鱼从朋友的小船劳伦·多萝西号的船舱里卸下来，与此同时，音乐声盖过了引擎的噪音。

youdao

Flemish enthusiasts at Steam Center Maldegem, a heritage center in northern Belgium, recently spent a cold day cutting spare boiler screws for their stable, which includes a Polish-built steam engine, the "General Maczek, " named for the Polish general who helped liberate Belgium in World War II.

WSJ: Belgian Train Museum Had a Hard Time Getting on Track