user: Question: How much Silver has a Rank of 4, and a Bronze smaller than 12?
Columns: ['Rank', 'Nation', 'Gold', 'Silver', 'Bronze', 'Total']
Types: ['text', 'text', 'real', 'real', 'real', 'real']
Sample row: ['1', 'Japan', 6.0, 1.0, 6.0, 13.0]
SQL:

assistant: SELECT SUM("Silver") FROM "Table" WHERE "Rank" = '4' AND "Bronze" < 12.0;