Mary often gets to school .A. ride her bikeB. by the bikeC. by a bikeD. on her bike

问题补充：

Mary often gets to school .

A. ride her bike

B. by the bike

C. by a bike

D. on her bike

答案：

A. ride her bike

B. by the bike

C. by a bike

(答案→)D. on her bike

解析：句意：玛丽经常骑自行车去上学。on her bike骑自行车，固定表达。