312194
He has trained well over 100 undergraduate students , 30 graduate students , and 20 postdoctoral fellows and visiting scientists in his laboratory .
 None
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:
 None