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Quadruple VS

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

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

Japanese Option A

強固

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

強烈

きょうれつ (kyōretsu)
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 "強固", "強烈", "強靭", "堅牢" based on context.
  • 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..
  • 強烈 (きょうれつ (kyōretsu) - Level: N2): Maps to "strong, intense, fierce" and is used when Refers to something very powerful, impactful, or severe, often in a sensory.
  • 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 "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 "強烈"
彼は強烈な個性を持っている。
He has a strong personality.
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: "その建物は地震にも耐えられる ___ な構造をしている。" (Meaning: "That building has a strong structure that can withstand earthquakes.")
🎉 Correct Answer!

Remember: "強固" is correct here because it represents "strong, firm, solid, robust" in the context: "That building has a strong structure that can withstand earthquakes.".

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