8005
Before about 1800 , due to the lack of airtight pads " ( see History ) " , practical woodwinds could have only a few keys to control accidentals ( notes outside their diatonic home scales ) .
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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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