This grammar shows a strong reason. It means 'because it's true that...' or 'it's clear that...'. You use it to explain why you say something, or to show strong feelings.
Clause + んだからPrimary
な-Adjective + なんだから
Noun + なんだから
This grammar shows a strong reason. It means 'because it's true that...' or 'it's clear that...'. You use it to explain why you say something, or to show strong feelings.
もう大人なんだから、自分のことは自分でしなさい。
You're an adult now, so take care of your own affairs.
あれだけ練習したんだから、きっと試合に勝てるよ。
We practiced that much, so I'm sure we can win the match.
まだ給料日じゃないんだから、無駄遣いはやめてよ。
It's not payday yet, so stop wasting money!
どうして返事をしないの？心配してるんだから！
Why aren't you replying? I'm worried!
せっかく日本に来たんだから、色々な所へ行ってみたいです。
Since I've gone to the trouble of coming to Japan, I'd like to try going to various places.
This is different from 'から' and 'ので'. Those just give reasons. '〜んだから' adds strong feelings. It means 'You should know this' or 'It's clear, right?'. '〜んだもん' is like a child's excuse. '〜んだから' is more like a strong statement or a demand.
Watch out: Do not use this with your boss. It is too casual. It can sound like a demand. Use "〜のですから" or "ので" instead. For words like "元気" (genki), say "元気なんだから" (genki nanda kara). Do not say "元気だんだから" (genki danda kara).
Use this when you want to give a strong reason. It shows that your reason is very clear. This helps explain why you are asking or telling someone something. It makes your words sound more firm.
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