a treacherous villain的用法和样例：
- A treacherous fellow is the Shark.
- That treacherous villain, as vicious as a viper, stopped at no evils.
- I know of you Red Wizards. You are a treacherous lot.
- A treacherous coward who betrayed his friends to save his own skin.
- This was a treacherous act of betrayal by the Irish.