what is the {start time} for {George Canning} has {position held} as {Secretary of State for Foreign and Commonwealth Affairs} ?
What was the date that George Canning began working as Secretary of State for Foreign and Commonwealth Affairs?
When did George Canning become Secretary of State for Foreign and Commonwealth Affairs?
SELECT ?t WHERE { ?d property:position_held resource:Secretary_of_State_for_Foreign_and_Commonwealth_Affairs . ?d property:start_time ?t . resource:George_Canning property:position_held ?d }
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} 

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