16315
In the Classical period , the subdominant is the only possible substitute for the tonic at this position ( because any other key would need resolution and would have to be introduced as a false reprise in the development ) , but with the erosion of the distinction between the sharp and flat directions and the blurring of tonal areas true recapitulations beginning in other keys became possible after around 1825 .
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Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
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