8933
Escort aircraft carriers , such as , were sometimes purpose-built but most were converted from merchant ships as a stop-gap measure to provide anti-submarine air support for convoys and amphibious invasions .
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Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: location, person, organization 
Text: {0} 
Answer:
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