Father sits by German river with old-fashioned young woman (7)
I believe the answer is:
damosel
'father sits by german river' is the definition.
I don't know anything about this answer so I cannot tell whether this works.
'with old-fashioned young woman' is the wordplay.
'with' means one lot of letters goes inside another.
'old-fashioned' becomes 'o' (this might be a standard abbreviation I've not previously seen).
'young woman' becomes 'damsel' (damsel is a kind of young woman).
'o' going inside 'damsel' is 'DAMOSEL'.
Can you help me to learn more?
(Other definitions for damosel that I've seen before include "Maiden, in poetry" , "Old term for young woman" .)