幸福闪现在脸上英语可以说是 "happiness flashes across one's face"。这个表达源自于人们面带微笑或幸福的神情，通常会伴随着快速而明显的脸部表情变化。例句：
When she saw her long-lost friend, happiness flashed across her face.
他一见到他多年未见的朋友，幸福的神情闪现在脸上。
As he crossed the finish pne, happiness flashed across his face.
当他跑过终点线时，幸福的神情闪现在他的脸上。
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