Table: yugoslav_football_results_4
Columns: date
city
opponent
results
type_of_game

Question: Which opponent had a result of 0:1?
SQL: SELECT "opponent" FROM yugoslav_football_results_4 WHERE "results" = '0:1'

Question: When was the game played in Zagreb?
SQL: SELECT "date" FROM yugoslav_football_results_4 WHERE "city" = 'zagreb'

Question: Which opponent played a 1990 wcq type of game, where the results were 0:0?
SQL: SELECT "opponent" FROM yugoslav_football_results_4 WHERE "type_of_game" = '1990 wcq' AND "results" = '0:0'

Question: When was the game played against Norway with a result of 1:0?
SQL: SELECT "date" FROM yugoslav_football_results_4 WHERE "opponent" = 'norway' AND "results" = '1:0'