I'll never forget the day when [on which] we first met.

我永远不会忘记我们第一次见面的那一天。

youdao

Do you still remember the day on which we met for the first time?

你还记得我们首次见面的那天吗？

youdao

Do you still remember the day on which we met for the first time?

你还记得我们首次见面的那天吗？

youdao