28916
Two types of modifications , namely , 2 ' - O , 4 ' - C - methylene - beta - d - ribofuranose ( beta - d - LNA ) and 2 ' - O , 4 ' - C - methylene - alpha - l - ribofuranose ( alpha - l - LNA ) , have been shown to yield RNA and DNA duplex - like structures , respectively .
 Chemical: 2 ' - O , 4 ' - C - methylene - beta - d - ribofuranose; Chemical: 2 ' - O , 4 ' - C - methylene - alpha - l - ribofuranose
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
 Entities: 2 ' - O , 4 ' - C - methylene - beta - d - ribofuranose, 2 ' - O , 4 ' - C - methylene - alpha - l - ribofuranose 
Answer:
 Chemical: 2 ' - O , 4 ' - C - methylene - beta - d - ribofuranose; Chemical: 2 ' - O , 4 ' - C - methylene - alpha - l - ribofuranose