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careless; sloppy; faulty
using unreliable sources (in a piece of writing); piece of writing with unreliable sources or many errors
杜撰な管理体制が事故の原因となった。
A sloppy management system was the cause of the accident.
杜撰な計画では成功は望めない。
You cannot hope for success with a careless plan.
報告書の内容が杜撰だと厳しく指摘された。
It was sternly pointed out that the report's content was sloppy.