Question: when {Bank of China} has {owned by} as {National Council for Social Security Fund} ?
Paraphrase: At what time was Bank of China was owned by National Council for Social Security Fund?
SPARQL (Wikidata): SELECT ?value WHERE { wd:Q484365 p:P69 ?s . ?s ps:P69 wd:Q21578 . ?s pq:P582 ?value}