Translation guide
The number 18. In Japanese, numbers are expressed using native Japanese or Sino-Japanese readings depending on context. For counting most things, the Sino-Japanese reading is standard.
十八
eighteen
Expressing the number eighteen in isolation, such as in math, phone numbers, or abstract counting.
Standard Sino-Japanese reading for the number 18. Used in most contexts: counting, math, phone numbers, etc.
十八足す二は二十です。
Eighteen plus two is twenty.
When counting objects, 十八 is often followed by a counter suffix (e.g., 個, 人, 枚). The reading of the number part remains じゅうはち.
りんごを十八個買いました。
I bought eighteen apples.
Stating someone's age as eighteen.
Referring to the 18th day of a month.
Counting 18 items using the generic counter 〜つ.
When 十八 (じゅうはち) combines with certain counters starting with さ, た, は, or か rows, the final ち may change to っ. For example, 十八歳 (じゅうはっさい) and 十八回 (じゅうはっかい).