ISORI

〜とたんに

JLPT N3:

the moment

"The moment X happened, Y": the second thing happened immediately after the first, usually unexpectedly.

How to form it

  • Put the verb in the た-form and add とたん or とたんに: 開(あ)けたとたん(に).
  • The second half is something that happened, often a surprise — not your own plan or intention.

Examples

ドアを開(あ)けたとたん、犬(いぬ)が飛(と)び出(だ)した。

The moment I opened the door, the dog shot out.

家(いえ)に着(つ)いたとたんに、雨(あめ)が降(ふ)り出(だ)した。

It started raining the moment I got home.

Notes

  • It is also written in kanji: 途端(とたん).

Common mistakes

  • Using the dictionary form. Say 開(あ)けたとたん, not 開(あ)けるとたん.
  • Using it for your own intention. Say 家(いえ)に帰(かえ)ったらすぐ寝(ね)よう, not 帰(かえ)ったとたんに寝(ね)よう.