火灾是由香烟的火花引起的。

The fire was caused by a ___spark from a cigarette.

当最后的火花停止闪烁时，所有人都起立唱起了国歌。

As the last ___spark ceased to glow, all the people stood up and sang the national anthem.

那个旧铁炉迸出一颗微小而明亮的火星，落在了壁炉前的地毯上。

The old iron stove threw out a tiny, bright ___spark that landed on the hearth rug.