A study on the usage of synonyms "nareru, najimu, shitashimu" -Focusing on the relationship between subject and object, such as the person, thing, and animal-.

This study analyzed the usage of synonyms "nareru, najimu, shitashimu". The analysis results are as follows. ①"Nareru" represents a change in state. Object promotes change, therefore subject changes. Accordingly, subject is the person, body part, and animal. Thing cannot be subject. "Nareru" has nuances of “not good at object, not fond of object at first". ②"Najimu" represents the result of a change in state. In other words, subject naturally (habitually) feels comfortable as time passes. "Najimu" does not have nuances of “not good at object, not fond of object at first". In the case of "najimu", subject is the person, thing, and body part. The causative form is often used. ③"Shitashimu" is used when subject enjoys object and acts positively. Therefore, only person can be subject. "Shitashimu" does not have nuances of “not good at object, not fond of object at first". The passive form is often used.