What is {educated at} of {Mao Zedong} that is {start time} is {1912-1-1} ?
Which school did Mao Zedong go to beginning January 1, 1912?
Which school did Mao Zedong attend starting January 1, 1912?
SELECT ?t WHERE { ?k property:educated_at ?t . FILTER ( CONTAINS ( YEAR ( ?x ) , '1912' ) ) . ?k property:start_time ?x . resource:Mao_Zedong property:educated_at ?k }
select distinct ?obj  where {
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> <http://wikidata.dbpedia.org/resource/Q5816> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#predicate> <http://www.wikidata.org/entity/P69> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#object> ?obj .
?statement <http://www.wikidata.org/entity/P580> <1912-1-1>
} 

SELECT ?obj WHERE { wd:Q5816 p:P69 ?s . ?s ps:P69 ?obj . ?s pq:P580 ?x filter(contains(YEAR(?x),'1912')) }