〜てからでないと
Not until 〜てからでないと
Meaning
"Not until ~", "unless ~ is done first" — a precondition that must come first.
Formation
[verb て-form] + からでないと / からでなければ
Notes
The second clause is always negative or an impossibility: 見てからでないと決められません. Close to 〜ないことには, but this one stresses the ORDER — the first thing has to happen before the second can.
Examples
実物（じつぶつ）を見（み）てからでないと決（き）められません。
I cannot decide until I have seen the real thing.
Breakdown
手（て）を洗（あら）ってからでないと食（た）べてはいけません。
You must not eat until you have washed your hands.
Breakdown
許可（きょか）を取（と）ってからでなければ使（つか）えません。
It cannot be used unless permission is obtained first.
Breakdown
説明（せつめい）を聞（き）いてからでないと分（わ）かりません。
I will not understand until I have heard the explanation.
Breakdown
十八（じゅうはち）歳（さい）になってからでないと運転（うんてん）できません。
You cannot drive until you turn eighteen.
Breakdown
⚠️ Often confused with
〜と、〜
Conditional と (whenever / when)
Two uses: (1) natural/habitual consequence — "whenever A happens, B happens"; (2) discover...
〜ば
Conditional 〜ば (if / whenever)
A general conditional — "if A, then B". Formed from the hypothetical form (仮定形) of the...
〜たら
Conditional 〜たら (if / when / after)
The most versatile conditional. "If/when A happens, B". Formed from the ta-form stem + ら....
〜なら
Conditional 〜なら (if / given that)
A conditional based on the listener's stated or known information — "if it's the case that...
〜ても / 〜でも
Even if 〜ても
"Even if A, B" / "no matter if A". Indicates that B happens regardless of A. The result is...
〜場合は
In case 〜場合は
"In the event that ~ / in the case that ~". Used to discuss what to do in a particular (of...
〜ないことには
Unless 〜ないことには
"Unless ~", "without first ~ing" — nothing can proceed until this happens.
〜としたら / 〜とすれば
Supposing 〜としたら
"Supposing ~", "if we assume ~" — reasoning from a hypothetical.
〜さえ〜ば
If only 〜さえ〜ば
"If only ~", "as long as just ~" — one sufficient condition.