Example: His boss is always GETTING AT him for arriving late.
Example: What do you think she's GETTING AT? I've no idea what she wants.
Meaning: Be able to reach, find, access
Example: It's on the top shelf and I can't GET AT it.
Meaning: Use threats, payments, bribes, etc, to affect someone's testimony or decision
Example: The gangsters GOT AT the jury, who found them not guilty of all charges despite the evidence presented in court.