短語詞組短語task difficulty index 任務(wù)難度指數(shù)difficulty index of caving 垮冒難度指數(shù)item difficulty index 試題難度指數(shù);難度指數(shù);難易度指標(biāo)Weaving Difficulty Index 織造難度系數(shù)operative difficulty index 操作難度Difficulty And Differentiation Index 難度區(qū)分度Difficulty index for apple 難易度指數(shù)index difficulty weighting 指標(biāo)難度賦權(quán)法index of difficulty 難度指數(shù) 返回 difficulty index