meet by chance 萍水相逢

“萍水相逢”，汉语成语，原义是浮萍因水而四处流荡，聚散不定；比喻人本素不相识，因机缘巧合偶然相逢。可以翻译为“meet by chance，a chance acquaintance”等。

例句：

我们萍水相逢，却很谈得来。

Although we have met by chance, we do have a lot in common.