てからでないと・
Use this construction when one action must be completed before another action, decision, or result becomes possible. It means “not until after” or “unless and until.”
A necessary first step
The first action is not simply earlier in time. Completing it is a genuine requirement: before that happens, the following action is impossible, unavailable, or cannot yet be decided.
Typical contexts
The construction is natural with physical requirements, official procedures, and information needed before a decision can be made.
この薬は食事をしてからでないと飲めません。
This medicine cannot be taken until after a meal.
Analyze本人確認が終わってからでなければ、口座を開設できません。
An account cannot be opened until identity verification is complete.
Analyze実際に現地を見てからでないと、移転するかどうかは決められない。
A decision about whether to relocate cannot be made until the site has been seen in person.
AnalyzeSequence versus necessity
てから alone simply places one event after another. The target construction adds that the second event cannot happen before the first is complete. A goal followed by には identifies something needed to achieve that goal, but it does not necessarily require a completed-first sequence. た上で can present a completed action or prior consideration as the basis for what follows and is more common in careful, formal contexts.
受付を済ませてから、会場に入りました。
After checking in, I entered the venue.
AnalyzeThis only reports the order of two completed actions; it does not explicitly state that entry was impossible beforehand.
More examples
安全カバーを閉めてからでないと、機械は動きません。
The machine will not operate until the safety cover is closed.
Analyze管理者の承認を得てからでなければ、このデータにはアクセスできない。
Access to this data is unavailable until administrator approval has been obtained.
Analyze検査結果が出てからでないと、原因はわかりません。
The cause will not be known until the test results are available.
Analyze候補者全員と話してからでなければ、採用する人は決められない。
The person to hire cannot be chosen until all the candidates have been spoken with.
Analyze契約内容を確認してからじゃないと、サインはできないよ。
Signing is not possible until the contract terms have been checked.
AnalyzeThe contracted form gives this sentence a conversational tone.
現物を確認してからでなければ、正確な査定は難しい。
An accurate appraisal is difficult until the actual item has been inspected.
Analyze