what is the {for work} for {Robert Frost} has {award received} as {Pulitzer Prize for Poetry} ?
When Robert Frost won the Pulitzer Prize for Poetry, what work was it for?
Name the type of work done by Robert Frost for which he has received award as Pulitzer Prize for Poetry?
SELECT ?r WHERE { resource:Robert_Frost property:award_received ?r . ?r property:for_work ?r . ?r property:award_received resource:Pulitzer_Prize_for_Poetry }
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