Table: countesses_flanders
Columns: name
father
birth
marriage
became_countess
ceased_to_be_countess
death
spouse

Question: When did the person born on 3 May 1446 cease to be countess?
SQL: SELECT "ceased_to_be_countess" FROM countesses_flanders WHERE "birth" = '3 may 1446'

Question: Who was the father of the person born in 1363?
SQL: SELECT "father" FROM countesses_flanders WHERE "birth" = '1363'

Question: When was the marriage of the person who died on 17 December 1471?
SQL: SELECT "marriage" FROM countesses_flanders WHERE "death" = '17 december 1471'