〜でなくてなんだろう

Isn't it...?; Isn't it supposed to be...?

1. Overview

「〜でなくてなんだろう」 is used to emphasize that something is as expected or should be the case, expressing confirmation of a phenomenon or action. It often carries a tone of emphasis and rhetorical questioning. It is typically used to affirm that something should naturally be a certain way, with a sense of questioning when it doesn't meet expectations.

2. Structure

1. Noun + でなくてなんだろう
   Used to emphasize that something should be a certain way, questioning its deviation from that state.

2. Verb (dictionary form) + でなくてなんだろう
   Used to express that an action should be done in a particular way, with a sense of questioning if it is not done that way.

3. Usage Explanation

• To express something that is natural or expected:
  This structure expresses that something should naturally be the case, and it questions the possibility of it being otherwise.

• With an emphasis and rhetorical questioning tone:
  The structure emphasizes the expected state of things and carries a rhetorical question, indicating surprise or disbelief if the expected situation is not the case.

• English translation:
  It can be translated as “Isn't it...?” or “Isn't it supposed to be...?”

4. Example Sentences

1. これだけの努力をしたのだから、成功しないでなくてなんだろう。
   Having made this much effort, isn't success supposed to be the result?

2. 彼の実力からして、この結果はでなくてなんだろう。
   Given his abilities, this result isn't supposed to happen, right?

3. あんなに親切にしてくれた彼女が裏切るなんて、そんなことはでなくてなんだろう。
   Someone as kind as her betraying me, that couldn’t be possible, right?

4. こんなに美味しい料理を食べて、幸せじゃないでなくてなんだろう。
   Eating such delicious food, isn’t it natural to feel happy?

5. あんなに練習したのだから、合格しないでなくてなんだろう。
   Having practiced so much, isn’t it expected to pass?

5. Key Points to Note

• Rhetorical Questioning Tone:
  This expression carries a strong rhetorical questioning tone, indicating that something should naturally be the case, and expressing surprise or confusion if it is not.

• Emphasis on Expectations:
  The phrase emphasizes that a particular outcome or situation is expected, and highlights the oddity or improbability of anything else occurring.

6. Similar Grammar

• 〜でないとしたら: Used to express that if something doesn’t meet a certain condition, other outcomes will follow.
  • Example: 彼が来ないとしたら、会議はどうするんだろう。
    If he doesn't come, what will happen to the meeting?

7. Alternative Grammar

• 〜であろう: Used to express a strong supposition that something should be the case.
  • Example: この道を歩けば、駅に着くだろう。
    If you walk this road, you should reach the station.

8. Summary

「〜でなくてなんだろう」 is used to emphasize that something is as expected or should naturally be the case. It often carries a rhetorical questioning tone, expressing surprise or disbelief when something does not align with what was anticipated. It is used to confirm the natural or expected state of things.