Every word in these three columns hides a secret–a concealed word in consecutive letter somewhere within it. Choose one word from each column to make a trio whose hidden words all belong to the same category. For example, you can form a trio out of MACHINATION, INCUBATE, and VAGABOND from the three columns, because they contain CHINA, CUBA, and GABON respectively: three countries. Can you find the other nine hidden themes?
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