CREATE TABLE "out" (
  "nat" text,
  "name" text,
  "moving_to" text,
  "type" text,
  "transfer_window" text,
  "transfer_fee" text,
  "source" text
);

Question: WHAT IS THE SOURCE WITH A TYPE OF TRANSFER AND MEX?
SQL: SELECT "source" FROM "out" WHERE "type"='transfer' AND "nat"='mex';

Question: WHAT IS THE NAME WITH BAYER LEVERKUSEN?
SQL: SELECT "name" FROM "out" WHERE "moving_to"='bayer leverkusen';

Question: WHAT NAME HAS A FREE TRANSFER FREE AND RETIRED?
SQL: SELECT "name" FROM "out" WHERE "transfer_fee"='free' AND "moving_to"='retired';

Question: WHAT TRANSFER FEE HAS A TYPE OF TRANSFER FOR DOS SANTOS?
SQL: SELECT "transfer_fee" FROM "out" WHERE "type"='transfer' AND "name"='dos santos';