user: Question: What is the average Silver, when Rank is 5, and when Bronze is less than 1?
Columns: ['Rank', 'Nation', 'Gold', 'Silver', 'Bronze', 'Total']
Types: ['real', 'text', 'real', 'real', 'real', 'real']
Sample row: [1.0, 'South Korea', 5.0, 4.0, 4.0, 13.0]
SQL:

assistant: SELECT AVG("Silver") FROM "Table" WHERE "Rank" = 5.0 AND "Bronze" < 1.0;