user: Question: I want the control trailers for 1931 with builder of GRCW
Columns: ['Year', 'Builder', 'Motors', 'Trailers', 'Control Trailers']
Types: ['text', 'text', 'text', 'text', 'text']
Sample row: ['1923', 'BRCW', '—', '1', '—']
SQL:

assistant: SELECT "Control Trailers" FROM "Table" WHERE "Year" = '1931' AND "Builder" = 'GRCW';