1.
weeks (duration)
A counter for counting the duration of time in weeks.
週間 is a counter for weeks of duration. It emphasizes the span of time rather than a specific week.
COUNTING:
- 一週間: one week (note the っ: いっしゅうかん)
- 二週間: two weeks
- 三週間: three weeks
- 何週間: how many weeks?
COMMON PATTERNS:
- 一週間前: one week ago
- あと一週間で: in one more week
- 二週間ぐらい: about two weeks
CONTRAST WITH 週:
週 refers to a specific week or the concept of "week" (先週 = last week, 来週 = next week, 毎週 = every week). 週間 is used specifically for counting duration in weeks.