a stroke of lightning.的用法和样例：
例句
- Harry was left with a scar in the shape of a lightning bolt on his forehead.
哈里前额留下了一个闪电形状的疤痕。 - A flash of lightning lit up the huddle of huts, and in the brilliant white glare she could see a number of people hurrying through the downpour.
一个闪电照得这一带的草棚雪亮，闪电光下看见大雨中有些人急急忙忙地走。
