Question: who was Colin Firth's partner as at 1989-1-1?
Paraphrase: Who was Colin Firth's partner on 1989-1-1?
SPARQL (Wikidata): SELECT ?obj WHERE { wd:Q162492 p:P451 ?s . ?s ps:P451 ?obj . ?s pq:P580 ?x filter(contains(YEAR(?x),'1989')) }