手早い答え
acontecer は日常的な「起こる」、ocorrer はより正式で報告調です。
確実な見分け方は、英語から訳す前に、その単語の働きを見きわめることです。
それぞれの単語の働き
acontecer
to happen
Use acontecer for events and situations in ordinary conversation.
ocorrer
to occur
Use ocorrer for events in neutral, formal, journalistic, or technical language.
選び方
- acontecer: Choose acontecer if the sentence points to events and situations in ordinary conversation.
- ocorrer: Choose ocorrer if the sentence points to events in neutral, formal, journalistic, or technical language.
例文
O que aconteceu ontem?
What happened yesterday?
O acidente ocorreu de madrugada.
The accident occurred before dawn.
よくある落とし穴
Ocorrer also has a separate use meaning “come to mind”: ocorreu-me uma ideia. Acontecer cannot replace it there.
文脈の中で練習する
自分の実生活から文を一つ選び、二回書いてみましょう。一度はacontecerで、もう一度はocorrerで。どちらも成り立ちそうなら、意味の違いを言葉にしてみましょう。