不忠诚

• be disloyal to

例句

1. 新总统对不忠诚的陆军军官进行了一次整肃。
   The new president carried out a purge of disloyal army officers.
2. 这话只跟你说，不要外传，我看他很不忠诚。
   Between you and me, I think he's rather disloyal.