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Quadruple VS

Synonym Boundary: "丈夫", "強固", "強靭", "堅牢"

All represent the core concept "strong", but require precise selection.

Japanese Option A

丈夫

じょうぶ (jōbu)
N5 / CEFR
Japanese Option B

強固

きょうこ (kyouko)
N2 / CEFR
Japanese Option C

強靭

きょうじん (kyōjin)
N1 / CEFR
Japanese Option D

堅牢

けんろう (kenrou)
N1 / CEFR

Quadruple VS Nuance Contrast & Social Differences

When expressing "strong" in Japanese, you must carefully distinguish between "丈夫", "強固", "強靭", "堅牢" based on context.
  • 丈夫 (じょうぶ (jōbu) - Level: N5): Maps to "strong, durable, healthy" and is used when A na-adjective used to describe objects that are sturdy and durable, or people who are healthy and robust. It implies resistance to damage or illness..
  • 強固 (きょうこ (kyouko) - Level: N2): Maps to "strong, firm, solid, robust" and is used when Used to describe physical structures, systems, or relationships that are durable, resistant, and difficult to break. Emphasizes stability and robustness..
  • 強靭 (きょうじん (kyōjin) - Level: N1): Maps to "strong, robust, resilient, tough" and is used when Describes something physically or mentally strong, durable, and resilient to external forces or difficulties. 物理的、精神的に強く、困難や外部からの力に耐えうるしなやかで丈夫なさまを表します。.
  • 堅牢 (けんろう (kenrou) - Level: N1): Maps to "strong; sturdy; robust; durable" and is used when Describes something physically very strong, resistant to damage, and built to last for a long time. Often used for structures, materials, or systems..
Mixing these up can easily lead to unnatural translations. Refer to the bilingual context cards below to master the boundaries!
Context for "丈夫"
この椅子はとても丈夫だ。
This chair is very sturdy.
Context for "強固"
その建物は地震にも耐えられる強固な構造をしている。
That building has a strong structure that can withstand earthquakes.
Context for "強靭"
彼の精神は、いかなる困難にも屈しない強靭さを持っている。
His spirit possesses a resilience that will not yield to any difficulty.
Context for "堅牢"
この金庫は非常に堅牢で、簡単に開けられない。
This safe is extremely sturdy and cannot be easily opened.

Synonym Mastery Challenge

Which Japanese word perfectly fits this blank space?

Fill in the blank: "この椅子はとても ___ だ。" (Meaning: "This chair is very sturdy.")
🎉 Correct Answer!

Remember: "丈夫" is correct here because it represents "strong, durable, healthy" in the context: "This chair is very sturdy.".

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