不 ㄅㄨ ˋ bù 辨 ㄅㄧㄢ ˋ biàn 菽 ㄕㄨ shū 麦 ㄇㄞ ˋ mài 不 ㄅㄨ ˋ bù 辨 ㄅㄧㄢ ˋ biàn 菽 ㄕㄨ shū 麥 ㄇㄞ ˋ mài lit. cannot tell beans from wheat (idiom); fig. ignorant of practical matters