Both the summer and the winter Olympic Games are held every four years on a basis.A. magi

问题补充：

Both the summer and the winter Olympic Games are held every four years on a basis.

A. magical

B. regular

C. familiar

D. logical

答案：

A. magical

(答案→)B. regular

C. familiar

D. logical

解析：句意，夏季奥运会和冬季奥运会都是按照规定，每四年举办一次。magical 魔力的 regular 有规律的 familiar 熟悉的 logical 逻辑的，根据题意，故选B。