Below is an instruction that describes a task. Write a response that appropriately completes the request.

### Instruction:
what is the time/retired when the laps is 6, the grid is less than 18 and the driver is clay regazzoni?

### Inputs:
table_name: table, columns: ['Driver', 'Constructor', 'Laps', 'Time/Retired', 'Grid']

### Response:
SELECT Time/Retired FROM table WHERE Laps = 6 AND Grid < 18 AND Driver = clay regazzoni