58053
Those who study contemporary language changes , such as William Labov , acknowledge that even a systematic sound change is applied at first unsystematically , with the percentage of its occurrence in a person 's speech dependent on various social factors .
 person: William Labov
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: William Labov 
Answer:
 person: William Labov