How to talk about Duration in Japanese
期間 /kikan/: Duration
For hours, add 時間 /jikan/ after the numbers. Some irregular readings:
4時間 /yo-jikan/: 4 hours
9時間 /ku-jikan/: 9 hours
*1時間半 /ichi-jikan-han/: one and a half hour (we normally say this instead of 1 時間30分 /ichi-jikan-san-jup-pun/)
→ 「何時間」/nan-jikan/: how many hours
For days, we will use the same words for days of the month like we have learnt in How to say Date in Japanese (pt.3), the attachment of 間 /kan/ is optional. However, there is one exception:
1日 /ichi-nichi/: 1 day (instead of /tsuitachi/)
→ 「何日」/nan-nichi/: how many days
For weeks, add 週間 /shūkan/ after the numbers. There are some irregular readings:
1週間 /isshūkan/: 1 week
8週間 /hasshūkan/: 8 weeks
10週間 /jusshūkan/ or /jisshūkan/: 10 weeks
→ 「何週間」/nan-shūkan/: how many weeks
For months, we will add ヵ月 /ka-getsu/ after the numbers, the attachment of 間 /kan/ is optional. Some irregular readings:
1ヶ月間 /ikka-getsu/: 1 month
6ヶ月間 /rokka-getsu/: 6 months = *半年 /hantoshi/: half a year
10ヶ月間 /jukka-getsu/ or /jikka-getsu/: 10 months
*1ヵ月半 /ikka-getsu-han/: a month and a half
→ 「何ヶ月」/nan-ka-getsu/: how many months
For years, add 年 /nen/ after the numbers, the attachment of 間 /kan/ is optional. There is only one irregular readings:
4年 /yo-nen/: 4 years
*1年半 /ichi-nen-han/: a year and a half
→ 「何年」/nan-nen/: how many years
Related Post:
Japanese Mealtime Vocabulary
Japanese Adverbs of Time