夏天的一个晚上，他正在院子里背一篇文章，忽然见许多萤火虫在低空中飞舞。
On one summer night , when he was practicing reading an article , he suddenly saw many fireflies lighting up the sky .
途中，我们碰巧发现一只萤火虫悠闲地在山间飞舞。
On the way , we stumbled upon a firefly dancing leisurely in the mountains .
萤火虫在飞舞