夜更けに正体不明の集団が研究所を襲撃した。
Late at night, an unidentified group attacked the research institute.
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Handwriting
Example sentences
An unidentified flying object was spotted in the sky last night.
正体不明の怪人が、夜な夜な街に現れるという噂がある。
There is a rumor that a mysterious person appears in the city night after night.
Usage Notes
A four-character compound (yojijukugo) describing something whose true nature or identity is not known.
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