🦅 Project Eagle
Quadruple VS

Synonym Boundary: "一つ", "片道", "億", "相次いで"

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

Japanese Option A

一つ

ひとつ (hitotsu)
N5 / CEFR
Japanese Option B

片道

かたみち (katamichi)
N4 / CEFR
Japanese Option C

おく (oku)
N3 / CEFR
Japanese Option D

相次いで

あいついで (aitsuide)
N2 / CEFR

Quadruple VS Nuance Contrast & Social Differences

When expressing "one" in Japanese, you must carefully distinguish between "一つ", "片道", "億", "相次いで" based on context.
  • 一つ (ひとつ (hitotsu) - Level: N5): Maps to "one (general counter for objects)" and is used when Used for counting general items, especially small, individual objects, when a specific counter is not needed or known..
  • 片道 (かたみち (katamichi) - Level: N4): Maps to "one way, single trip" and is used when Describes a journey to a destination without returning. Often used with きっぷ.
  • (おく (oku) - Level: N3): Maps to "one hundred million (100,000,000)" and is used when A large numerical unit in Japanese. 1億 = 100,000,000. Often used for large amounts of money, population, or astronomical figures..
  • 相次いで (あいついで (aitsuide) - Level: N2): Maps to "one after another; in succession" and is used when Describes multiple events or incidents happening consecutively. Often used for significant or repeated occurrences..
Mixing these up can easily lead to unnatural translations. Refer to the bilingual context cards below to master the boundaries!
Context for "一つ"
りんごを一つください。
Please give me one apple.
Context for "片道"
彼は飛行機の片道チケットしか持っていませんでした。
He only had a one-way flight ticket.
Context for "億"
日本の人口は約1億2千万です。
Japan's population is approximately 120 million.
Context for "相次いで"
事故が相次いで発生した。
Accidents occurred one after another.

Synonym Mastery Challenge

Which Japanese word perfectly fits this blank space?

Fill in the blank: "りんごを ___ ください。" (Meaning: "Please give me one apple.")
🎉 Correct Answer!

Remember: "一つ" is correct here because it represents "one (general counter for objects)" in the context: "Please give me one apple.".

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