一変

いっぺん

complete change

JLPT N1

Character Breakdown

Meaning and Usage

"一変" (いっぺん) means a complete or sudden change, often used to describe a drastic shift in situation, attitude, or condition. It is a noun that can be used with verbs like する (to do) to express that something has changed entirely.

Common Contexts

This word is frequently used in news reports, conversations about weather, emotions, or situations where a notable transformation occurs. For example, a person's mood or the weather can 一変, indicating a sharp and noticeable change.

Collocations and Patterns

  • 一変する: to change completely
  • 一変した態度: a completely changed attitude
  • 状況が一変する: the situation changes drastically

Register and Nuance

"一変" is neutral and can be used in both formal and informal contexts. It emphasizes the totality of the change rather than a gradual or partial shift.

Common Mistakes

Learners sometimes confuse 一変 with words that mean "slight change" or "gradual change." Remember, 一変 implies a sudden and complete transformation, not a subtle or slow one.

Example Sentences

かれのたいどはいっぺんした。

His attitude completely changed.

てんきがいっぺんして、きゅうにあめがふりだした。

The weather changed completely, and suddenly it started to rain.

じょうきょうがいっぺんしたため、けいかくをみなおすひつようがある。

Because the situation changed completely, it is necessary to review the plan.