5074
He is an expert on Baltic and Slavic languages , the Indo-European languages in general , and Proto-Indo-European , though he has also published studies of languages in many other language families .
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Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: location, person, organization 
Text: {0} 
 Entities:  
Answer:
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