CREATE TABLE "previous_winners" (
  "year" real,
  "best_teenage_young_adult" text,
  "reader_s_vote" text,
  "best_non_fiction" text,
  "lifetime_achievement" text
);

Question: How many times was the reader's vote na and the lifetime achievement na?
SQL: SELECT COUNT("year") FROM "previous_winners" WHERE "reader_s_vote"='na' AND "lifetime_achievement"='na';

Question: who won the lifetime achievement in the year 1998?
SQL: SELECT "lifetime_achievement" FROM "previous_winners" WHERE "year"=1998;

Question: who won the lifetime achievement when the best non-fiction is na, reader's vote is ne and the year is after 2005?
SQL: SELECT "lifetime_achievement" FROM "previous_winners" WHERE "best_non_fiction"='na' AND "reader_s_vote"='na' AND "year">2005;

Question: what is the reader's vote for 2011?
SQL: SELECT "reader_s_vote" FROM "previous_winners" WHERE "year"=2011;