user: Question: Who was the away team against the home team Sheffield United?
Columns: ['Tie no', 'Home team', 'Score', 'Away team', 'Date']
Types: ['text', 'text', 'text', 'text', 'text']
Sample row: ['1', 'Blackpool', '2–1', 'Manchester City', '7 January 1984']
SQL:

assistant: SELECT "Away team" FROM "Table" WHERE "Home team" = 'Sheffield United';