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

### Instruction:
Which Surface has Semifinalists of wally masur malivai washington?

### Inputs:
table_name: table, columns: ['Tournament', 'Surface', 'Week', 'Winner and score', 'Finalist', 'Semifinalists']

### Response:
SELECT Surface FROM table WHERE Semifinalists = wally masur malivai washington