Where two or more values match condition?

Where two or more values match condition?

I have been asked this question;
You list county names and the surnames of the representatives if the
representatives in the counties have the same surname.
and I have the following tables;
***REPRESENTATIVE***
REPI SURNAME FIRSTNAME COUNTY CONS
---- ---------- ---------- ---------- ----
R100 Gorege Larry kent CON1
R101 shneebly john kent CON2
R102 shneebly steve kent CON3
I cant seem to figure out the correct way to ask Orical to display a
surname that exists more then twice and the surnames are in the same
country.
I know how to ask WHERE something = something, but that's doesn't ask what
I want to know.