Database: movies_4
Question: Write down the release date of the movies produced by Twentieth Century Fox Film Corporation.
SQL: SELECT T3.release_date FROM production_company AS T1 INNER JOIN movie_company AS T2 ON T1.company_id = T2.company_id INNER JOIN movie AS T3 ON T2.movie_id = T3.movie_id WHERE T1.company_name = 'Twentieth Century Fox Film Corporation'