反義詞前綴是im，impublic中文意思是adj，不公開的，非大衆的
例如
The park is now open to the public.那公園現在對公衆開放了。
She retreated from public life.她放棄了社會生活。
Cost management of military industrial research public institution has been a weak point for a long time.長期以來軍工科研事業單位成本管理一直是一個弱項。
