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Other major rivers include the Xi , Mekong , Brahmaputra and Amur .
 Xi, Mekong, Brahmaputra, Amur
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
 Xi, Mekong, Brahmaputra, Amur