Study former currency in a foreign country (7)
I believe the answer is:
denmark
'foreign country' is the definition.
'denmark' can be an answer for 'country' (Denmark is an example). I am not sure about the 'foreign' bit.
'study former currency' is the wordplay.
'study' becomes 'den' (term for a study or office).
'former currency' becomes 'mark' (I have seen 'old currency' mean 'mark' so perhaps 'currency' could also mean 'mark'. I am not sure about the 'former' bit.).
'den'+'mark'='DENMARK'
'in a' acts as a link.
Can you help me to learn more?
(Other definitions for denmark that I've seen before include "Hamlet, Prince of . . . . . . . (7)" , "Ditto" , "Mark end of the country" , "A country of dark men?" , "Copenhagen its capital" .)