user: Question: what's the cylinders/ valves with model being 1.8 20V
Columns: ['model', 'cylinders/ valves', 'displacement cc', 'max. power kW (PS) at rpm', 'max. torque (Nm) at rpm', 'engine code', 'top speed (km/h)', 'production period']
Types: ['text', 'text', 'real', 'text', 'text', 'text', 'real', 'text']
Sample row: ['1.4 16V', 'R4/16', 1390.0, '55 (75) / 5,000', '126 / 3,800', 'AHW / AXP / AKQ / APE / AUA / BCA', 170.0, '1999–2004']
SQL:

assistant: SELECT "cylinders/ valves" FROM "Table" WHERE "model" = '1.8 20V';