The Great Wall travels deep valleys, deserts and mountains.
A. over; across; through
B. through; across; over
C. across; over; through
D. through; across; across
网友回答
A. over; across; through
(答案→)B. through; across; over
C. across; over; through
D. through; across; across
解析：介词辨析。Through穿过；across从表面横过；over从上方越过；句意：长城穿过深深的峡谷，横过沙漠，越过高山。故B正确。