Meaning
Shows a limited span of time within which one completed action happens.
Formation
- Same forms plus に: one short action inside the span: 出かけているあいだに掃除しました
When to use it
- Core use
- A single moment within that span
Example
母が出かけているあいだに部屋を掃除しました
While my mother was out, I cleaned the room.
Important notes
- Pay attention to the word form before the construction and to the particles around it.
Common mistakes
- Do not translate the pattern word for word; first identify its function in the whole situation.