かつては英語で
once

英語の定義

かつて
1. adv. once, before, formerly, former
私はかつてアイスランドに住んだことがある。 - I once lived in Iceland.
かつてのよう。 - Like it once was.
かつての友との再会。 - A reunion with someone who was once a friend.
京都はかつて日本の首都でした。 - Kyoto was once Japan's capital.
2. adv. (with a negative verb) never

once
1. adv. (frequency) One and only one time.
I have only once eaten pizza.
2. adv. (temporal location) Formerly; during some period in the past.
He was once the most handsome man around. I once had a bicycle just like that one.
Wang notes that flowers have rooted and grow in the area once covered with ice.
3. adv. (mathematics) Multiplied by one: indicating that a number is multiplied by one.
Once three is three.
4. adv. As soon as.
5. adv. (obsolete) At a future time.
6. conj. As soon as; when; after.
We'll get a move on once we find the damn car keys!
Once you have obtained the elven bow, return to the troll bridge and trade it for the sleeping potion.
Once he is married, he will be able to claim the inheritance.