週間(しゅうかん)

週間(しゅうかん) is a counter for weeks of duration. It emphasizes the span of time rather than a specific week.

Counting patterns

• 一(いっ)週間(しゅうかん): one week (note the っ: いっしゅうかん)
• 二(に)週間(しゅうかん): two weeks
• 三(さん)週間(しゅうかん): three weeks
• 何(なん)週間(しゅうかん): how many weeks?

Common patterns

• 一(いっ)週間(しゅうかん)前(まえ): one week ago
• あと一(いっ)週間(しゅうかん)で: in one more week
• 二(に)週間(しゅうかん)ぐらい: about two weeks

CONTRAST WITH 週(しゅう):
週(しゅう) refers to a specific week or the concept of "week" (先週(せんしゅう) = last week, 来週(らいしゅう) = next week, 毎週(まいしゅう) = every week). 週間(しゅうかん) is used specifically for counting duration in weeks.