CREATE TABLE table_name_50 (opponent VARCHAR2, date VARCHAR2, score VARCHAR2)

Name the opponent for jul 31 and score of w 5-1
SELECT opponent FROM table_name_50 WHERE date = "jul 31" AND score = "w 5-1"
SELECT "opponent" FROM "table_name_50" WHERE "date" = "jul 31" AND "score" = "w 5-1"