I would finally leave after the German mock (6)
I believe the answer is:
deride
'mock' is the definition.
(deriding is a kind of mocking)
'i would finally leave after the german' is the wordplay.
'i would' becomes 'I'd'.
'finally' suggests the final letters.
'after' is a charade indicator (letters next to each other).
'the german' becomes 'der' ('the' in German).
The final letter of 'leave' is 'e'.
'id'+'e'='ide'
'ide' put after 'der' is 'DERIDE'.
(Other definitions for deride that I've seen before include "Ridicule, scoff at" , "Ridicule, laugh at" , "Mock and jeer" , "Knock" , "Mock, scorn" .)