What is {twinned administrative body} of {Berlin} that is {start time} is {1992-8-28} ?
What is { Berlin's twinned administrative body } that is { start time } is { 1992 - 8 - 28 }?
SELECT ?obj WHERE { wd:Q64 p:P190 ?s . ?s ps:P190 ?obj . ?s pq:P580 ?x filter(contains(YEAR(?x),'1992')) }
select distinct ?obj  where {
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> <http://wikidata.dbpedia.org/resource/Q64> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#predicate> <http://www.wikidata.org/entity/P190> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#object> ?obj .
?statement <http://www.wikidata.org/entity/P580> <1992-8-28>
} 

When did Berlin's twinned administrative body start on August 28th, 1992?