National river, just as you'd expect (7)
I believe the answer is:
natural
'as you'd expect' is the definition.
I can't tell whether this defines the answer.
'national river' is the wordplay.
'national' becomes 'nat'.
'river' becomes 'ural' (Russian river).
'nat'+'ural'='NATURAL'
'just' acts as a link.
Can you help me to learn more?
(Other definitions for natural that I've seen before include "Inborn; unaffected" , "Unaffected or earthy" , "Unaffected, normal in manner" , "Regular" , "Not artificial or man-made" .)