user: Question: What are the former counties of the Great Grimsby district?
Columns: ['District', 'Status', 'Date abolished', 'Former county', 'Successor']
Types: ['text', 'text', 'text', 'text', 'text']
Sample row: ['Alnwick', 'non-metropolitan district', '1 April 2009', 'Northumberland', 'Northumberland']
SQL:

assistant: SELECT "Former county" FROM "Table" WHERE "District" = 'Great Grimsby';