104407
The eight first-wave accession countries , which joined the European Union on 1 May 2004 ( the Czech Republic , Estonia , Hungary , Latvia , Lithuania , Poland , Slovakia , Slovenia ) and the two second-wave accession countries that joined on 1 January 2007 ( Romania and Bulgaria ) , have completed the transition process .
 European Union, Czech Republic, Estonia, Hungary, Latvia, Lithuania, Poland, Slovakia, Slovenia, Romania, Bulgaria
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: media, plant, vehicle, astronomical object, time, disease, animal, location, person, organization, mythical figure, food, biology, geographical phenomenon, instrument, event 
Text: {0} 
Answer:
 European Union, Czech Republic, Estonia, Hungary, Latvia, Lithuania, Poland, Slovakia, Slovenia, Romania, Bulgaria