「〜わけだ」- Logical Conclusion

Explanation

The grammatical structure 〜わけだ is used in Japanese to express a logical conclusion or inevitability based on a given situation. It conveys a sense of "it makes sense" or "it’s only natural" by explaining why something is the way it is.

Grammar Pattern

Grammar Point	Connection	Explanation
〜わけだ	Verb plain form + わけだ	Used to express a logical conclusion based on a situation.
〜わけだ	い-Adjective plain form + わけだ	Used to express a logical conclusion based on a situation.
〜わけだ	な-Adjective / Noun + な/である/という + わけだ	Used to express a logical conclusion based on a situation.

Basic Usage

• Explaining Reasons: Used to explain why something happened.

  • 彼かれは毎日まいにち10時間じかん勉強べんきょうしていたわけだから、試験しけんに合格ごうかくできたんだ。
  • Kare wa mainichi 10-jikan benkyou shiteita wake da kara, shiken ni goukaku dekita nda.
  • He studied 10 hours every day, so it’s no wonder he passed the exam.
    
  • エアコンえあこんが壊こわれているわけだから、部屋へやが暑あついんだ。
  • Eakon ga kowarete iru wake da kara, heya ga atsui nda.
  • The air conditioner is broken, so it’s no wonder the room is hot.
    

• Drawing Conclusions: Used to naturally derive a conclusion based on prior information.

  • 彼女かのじょの父ちちは私わたしの母ははの弟おとうとだ。つまり、彼女かのじょと私わたしは従兄弟いとこになるわけだ。
  • Kanojo no chichi wa watashi no haha no otouto da. Tsumari, kanojo to watashi wa itoko ni naru wake da.
  • Her father is my mother’s younger brother. In other words, she and I are cousins.
    

Deep Dive

The structure 〜わけだ emphasizes that a result is obvious or natural, highlighting the logical coherence behind the fact.

• Examples:
  • 彼かれは毎日まいにち練習れんしゅうしていたわけだから、試験しけんに合格ごうかくできたんだ。
  • Kare wa mainichi renshuu shiteita wake da kara, shiken ni goukaku dekita nda.
  • He practiced every day, so it’s no wonder he passed the exam.
    
  • 彼女かのじょは忙いそがしいわけだから、会あえないんだ。
  • Kanojo wa isogashii wake da kara, aenai nda.
  • She’s busy, so it’s no wonder I can’t meet her.
    

Real-Life Scenarios

• Explaining Causes: Used to explain the reason behind a phenomenon or result.
  • 彼かれは毎日まいにち練習れんしゅうしていたわけだから、試験しけんに合格ごうかくできたんだ。
  • Kare wa mainichi renshuu shiteita wake da kara, shiken ni goukaku dekita nda.
  • He practiced every day, so it’s no wonder he passed the exam.
    
• Drawing Inferences: Used to derive a reasonable conclusion based on known information.
  • 彼女かのじょの父ちちは私わたしの母ははの弟おとうとだ。つまり、彼女かのじょと私わたしは従兄弟いとこになるわけだ。
  • Kanojo no chichi wa watashi no haha no otouto da. Tsumari, kanojo to watashi wa itoko ni naru wake da.
  • Her father is my mother’s younger brother. In other words, she and I are cousins.
    

Summary

The structure 〜わけだ is an effective way to summarize and explain the inevitability or logic behind a situation. In everyday conversations, using this structure can make your explanations clearer and more logical.