Denshi Jisho — Online Japanese dictionary

区別 くべつ distinction; differentiation; classification
Common word, Noun, Suru verb 
区別がつく くべつがつく to tell X from Y; to distinguish; to know (one thing) from (another)
Expression, Godan verb with ku ending 
区別が付く くべつがつく to tell X from Y; to distinguish; to know (one thing) from (another)
Expression, Godan verb with ku ending 
区別せずに くべつせずに without distinction; with no distinction
Expression 
区別がつかない くべつがつかない unable to tell apart
Expression 
区別が付かない くべつがつかない unable to tell apart
Expression 

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