Here are some synonyms for "admonish":
* Reprimand
* Rebuke
* Scold
* Warn
* Caution
* Upbraid
Here are some examples of how "admonish" can be used:
* "The teacher admonished the students for talking during the test."
* "The doctor admonished the patient for not taking their medication as prescribed."
* "The judge admonished the defendant for their reckless driving."
Key takeaway: Admonishing someone is about expressing disapproval and urging them to do better. It's a more serious form of advice than simply suggesting something.