Translation guide
The English word 'decade' refers to a period of ten years. In Japanese, the most common way to express this is with the counter 年 (ねん) preceded by the number 十 (じゅう), forming 十年 (じゅうねん). However, depending on context, other expressions like 年代 (ねんだい) for specific decades (e.g., the 1980s) or 10年間 (じゅうねんかん) for a duration of ten years are used.
Expressing a span of ten years in a general sense, such as 'for a decade' or 'over the past decade'.
This town has changed a lot in a decade.
He has lived in Japan for over a decade.
Emphasizes the duration of ten years. The suffix 間 (かん) explicitly marks a time span. Often used when focusing on the length of time.
A decade of hard work paid off.
A more literary or formal expression meaning 'a period of ten years', often implying the passage of time.
A decade has passed.
Referring to a named decade, like 'the 1990s' or 'the twenties'.
Used after a year or era to indicate a specific decade. For example, 1980年代 means 'the 1980s'. It can also be used with age decades like 20代 (はたちだい) for 'one's twenties'.
I like music from the 1990s.
Counting decades, such as 'several decades' or 'for decades'.
Means 'several decades' or 'decades'. The prefix 数 (すう) indicates an unspecified number, and 十年 means 'ten years'.
research spanning several decades
This building has been abandoned for decades.
Emphasizes a long period of decades, often with a sense of 'for many decades'. 何 (なん) means 'what' or 'how many', and も adds emphasis.
十年 (じゅうねん) is the general term for a decade. 10年間 (じゅうねんかん) explicitly marks a duration and is often used when emphasizing the length of time. 年代 (ねんだい) is used for specific decades like the 1980s or age ranges like one's 30s.
In Japanese, decades are often written with Arabic numerals, especially in horizontal text. For example, 10年 is common, but 十年 is also acceptable. For specific decades, 1990年代 is standard.
He is in his forties.
an event from decades ago