Translation guide
Expressing that something takes or lasts for a long duration. Japanese uses various time-related nouns, adverbs, and patterns depending on whether you mean 'for a long time', 'a long time ago', or 'it's been a long time'.
Describing an action or state that continues for a long period.
The most common and neutral way to say 'for a long time'. Literally 'long interval'.
長い間お待たせしました。
Sorry to have kept you waiting for a long time.
彼は長い間入院していた。
He was in the hospital for a long time.
Emphasizes the length of time as a quantity. Often used with verbs like かかる (take time).
その仕事は長い時間がかかった。
That work took a long time.
A compound noun meaning 'long time', often used in formal or written contexts, or as an adverb with に.
長時間の会議で疲れた。
I got tired from the long meeting.
Adverb meaning 'all along', 'the whole time', or 'for a long time continuously'. Implies an unbroken duration.
ずっと待っていた。
I was waiting for a long time.
Referring to something that happened far in the past.
Literally 'far before'. A natural way to say 'a long time ago'.
ずっと前にその映画を見た。
I saw that movie a long time ago.
Means 'old times' or 'long ago'. Can be used as a noun or adverb (昔に).
昔、ここは海だった。
A long time ago, this place was the sea.
Means 'quite a while ago', emphasizing that a considerable amount of time has passed.
だいぶ前に引っ越しました。
I moved a long time ago.
Greeting someone you haven't seen for a while.
Polite phrase meaning 'It's been a long time'. Used when meeting someone after a while.
お久しぶりです。お元気でしたか。
It's been a long time. How have you been?
Casual version of the above. Used among friends.
久しぶり！元気だった？
Long time no see! How have you been?
Very formal expression for 'It's been a long time', often used in letters or business contexts.
ご無沙汰しております。
It's been a long time. (formal)
Expressing that an action requires a long duration.
Standard phrase meaning 'it takes time'. Add 長い (long) to emphasize.
その準備には長い時間がかかる。
The preparations take a long time.
Means 'it takes time and effort', implying a troublesome or laborious process.
この料理は手間がかかる。
This dish takes a long time (and effort) to make.
English 'a long time' is often not directly translated as a single noun. Instead, Japanese uses time expressions like 長い間, 長時間, or adverbs like ずっと. Using 長い時間 is possible but may sound unnatural in some contexts.