CREATE TABLE "lone_star_series" (
  "date" text,
  "winning_team" text,
  "score" text,
  "winning_pitcher" text,
  "losing_pitcher" text,
  "attendance" real,
  "location" text
);

Question: Which location has a date of may 21?
SQL: SELECT "location" FROM "lone_star_series" WHERE "date"='may 21';