次第だ / 次第で【しだいだ】

The grammar pattern 次第だ / 次第で expresses that something depends on a particular factor. It conveys the idea that the outcome or result changes based on the preceding noun. It is similar to saying "it depends on ~" or "depending on ~" in English.

次第だ – "It depends on ~"

When しだい次第だ comes at the end of a sentence, it states that the outcome hinges entirely on the noun that precedes it.

This usage emphasizes that the preceding noun is the decisive factor.

次第で – "Depending on ~"

When しだい次第で is used mid-sentence, it connects to the following clause and means "depending on ~", indicating that something will vary or change according to the preceding factor.

A related form is 次第では, which adds a nuance of "in certain cases depending on ~", suggesting that under some conditions a particular outcome may arise.

Important notes

• 次第 attaches directly to nouns – no particle is needed between the noun and 次第. For example: かんがえ考えかた方しだい次第、つかいかた使い方しだい次第、あなたしだい次第.
• Be careful not to confuse this with the grammar pattern V[stem] + 次第 (meaning "as soon as"), which has a different meaning entirely.
• This expression is used in both spoken and written Japanese and carries a somewhat formal tone.