What a great artist! It seemed only a couple of minutes he had finished this wonderful painting!
A. until
B. when
C. after
D. before
网友回答
A. until
B. when
C. after
(答案→)D. before
解析：考查固定句型：It was/seemed+一段时间+before….，（好像）要….长时间就/才….，
句意：多么伟大的科学家啊！好像只要几分钟就完成了精美的画。A．until直到B．when当…时候C．after 在…后面，不符合句意：选D。