[ Military ] Open Question : What did British pioneer corps do in WWII?

I'm finding out about my great great uncle for school and he was in the Pioneer corps from 1940 but he was killed on his day off in1941. I want to know what the pioneer corps did in those few years he was in service. Please help if you have any info! Thanks! :)

Source: http://answers.yahoo.com/question/index?qid=20120107065832AAhtsrj

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