2088
These first British heavy tanks of World War I moved on caterpillar tracks that had substantially lower ground pressure than wheeled vehicles , enabling them to pass the muddy , pocked terrain and slit trenches of the Battle of the Somme .
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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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