user: Question: Which Opposing Team has an Against smaller than 19, and a Date of 20/05/1979?
Columns: ['Opposing Team', 'Against', 'Date', 'Venue', 'Status']
Types: ['text', 'real', 'text', 'text', 'text']
Sample row: ["Japan 'B'", 7.0, '10/05/1979', 'Tokyo', 'Tour Match']
SQL:

assistant: SELECT "Opposing Team" FROM "Table" WHERE "Against" < 19.0 AND "Date" = '20/05/1979';