Thepioneertypewasthecharacteristiconeattheturnoftheseventeenthcenturyandalsofitthebeginningofthe______(twenty)century,butitismuchlessevidenttoday.
正确答案:twentieth[解析]the+序数词。

Thepioneertypewasthecharacteristiconeattheturnoftheseventeenthcenturyandalsofitthebeginningofthe______(twenty)century,butitismuchlessevidenttoday.
正确答案: