Abstract: Chinese double-syllable words are formed by combining words without a linear syntax structure，which mainly consist of three categories：“monosyllable word+monosyllable word”→double-syllable word，which is formed by paratactic synonyms or by nonsynonyms；“monosyllable word+ monosyllable nonword”→double-syllable word，which is formed by
roots and affixes；double-syllable word→double-syllable word，which includes content word that changes into other part of speech or into function word.This paper examines the degree of applicability of these morphological approaches in all parts of speech and gives examples respectively.

Key words: double-syllable word, word-formation approach, morphology, degree of applicability