问题补充:
An interesting suggestion on how to measure the temperature on the moon has been .
A. put on
B. put out
C. put down
D. put forward
答案:
A. put on
B. put out
C. put down
(答案→)D. put forward
解析:考查短语辨析。put on穿;put out出版,扑灭;put down镇压;put forward提出。Put forward a suggestion提出建议。根据句意选D。