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When Chen arrived in Costa Rica on the 18th , his hosts departed from the pattern of the past few years by promising to support the ROC s bid for membership in the United Nations .
 person: Chen; geographical social political: Costa Rica; ordinal: 18th; date: the past few years; geographical social political: ROC; organization: the United Nations
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: date, organization, person, geographical social political, national religious political, facility, cardinal, location, work of art, law, event, product, ordinal, percent, time, quantity, money, language 
Text: {0} 
Answer:
 person: Chen; geographical social political: Costa Rica; ordinal: 18th; date: the past few years; geographical social political: ROC; organization: the United Nations