Show me perpetrators' names.
select t1.name from people as t1 join perpetrator as t2 on t1.people_id = t2.people_id;
Among the result, who are in "South Korea"?
select t1.name from people as t1 join perpetrator as t2 on t1.people_id = t2.people_id where t2.country = "South Korea";
How about China or Japan?
select t1.name from people as t1 join perpetrator as t2 on t1.people_id = t2.people_id where t2.country = "China" or t2.country = "Japan"