GrammarJLPT N5
〜さい
→ ... years old
… Years Old (Age Counter)
JLPT N5CounterNeutral
〜歳 (さい) is the standard counter used to express a person's age in Japanese. It attaches directly to a number to mean '… years old.' The kanji 歳 is the formal way to write it, though the simplified kanji 才 is also widely used, especially in casual writing, because 歳 has many strokes. Certain numbers have irregular or special readings when combined with 〜歳: notably 一歳 (いっさい), 八歳 (はっさい), and 十歳 (じゅっさい / じっさい), where the pronunciation of the number changes due to sound-change rules (音便). The question word for age using this counter is 何歳 (なんさい), meaning 'how old.' Unlike the native Japanese counting system using 〜つ (which can only be used for ages one through nine, plus とお for ten), 〜歳 can be used for any age and is the most common and universally understood way to state age in both spoken and written Japanese.
Examples
Example #1
私は二十歳です。
This is the most basic use of 〜歳, where you state your own age. The number comes directly before 歳 with no particle in between. Note that 二十歳 has the special reading はたち in addition to the regular にじゅっさい, and はたち is very commonly used since 20 is the traditional age of adulthood in Japan.I am 20 years old.
Structures
- Number + 歳
- Number + 歳 (さい)
Common mistakes
The most common mistake learners make with 〜歳 is forgetting the irregular sound changes: 一歳 is いっさい (not いちさい), 八歳 is はっさい (not はちさい), and 十歳 is じゅっさい or じっさい (not じゅうさい). Another frequent error is confusing 〜歳 with 〜年 (ねん); remember that 〜歳 counts age while 〜年 counts years as a duration or calendar year. Some learners also mistakenly add a particle between the number and 歳, such as saying 二十の歳, which is incorrect — the number attaches directly to 歳. Finally, while 才 and 歳 are interchangeable in meaning, be aware that 才 is considered more casual and may not be appropriate in very formal documents.
Related
〜才〜つ (counter)〜年 (ねん)〜か月何歳