user: Question: What is the listed surface for the Championship of Toronto that had a Runner-up outcome?
Columns: ['Outcome', 'Year', 'Championship', 'Surface', 'Partner', 'Opponents', 'Score']
Types: ['text', 'real', 'text', 'text', 'text', 'text', 'text']
Sample row: ['Winner', 2010.0, 'Indian Wells', 'Hard', 'Rafael Nadal', 'Daniel Nestor Nenad Zimonjić', '7–6 (10–8) , 6–3']
SQL:

assistant: SELECT "Surface" FROM "Table" WHERE "Outcome" = 'Runner-up' AND "Championship" = 'Toronto';