在中日两种语言中,助动词“可以”表示“许可”时,常被解释为「してもいい」,「してもいい」与“可以”在具体的语言环境或会话中,根据说话者、听话者以及场景等要素的不同会分别产生不同的引申意义。本文对「してもいい」与“可以”两者在引申意义上表现出的不同及其原因进行了分析。两者的使用出现不同主要是因为「してもいい」中还较多的保留了「しても+いい」这种复句性特征。 In both Chinese and Japanese, the auxiliary verb “can ” indicates “permission ”, which is often interpreted as “し て も い い”, “shi て mo い い” and “can” in a specific locale Or conversation, according to the speaker, listener and the scene will have different elements of different extension. This paper analyzes the differences and their causes in the extended meaning between “し て も い い” and “can”. The difference between the two is mainly due to the fact that the more complex features of “shi て mo い い” are retained in “shi て mo い い.”