本文选取在对外汉语教学中易混的一组副词“曾经”和“已经”为研究对象,从句法、语义和语用三个平面进行本体研究,运用大量语料,通过对比分析来展示这组易混副词的差异,以期为汉语教学尤其是对外汉语教学提供一定的参考依据。 This thesis chooses a group of adverbs such as “once” and “already” which are easy to be mixed in the teaching of Chinese as a Foreign Language, and studies the ontology from syntactic, semantic and pragmatic levels. By using a large number of corpora, The differences of this group of adverbial adverbs are displayed, with a view to providing some reference for teaching Chinese, especially for teaching Chinese as a foreign language.