He studied hard and pass the examination . A. could able toB. couldC. was able to D. ough

问题补充：

He studied hard and pass the examination .

A. could able to

B. could

C. was able to

D. ought

答案：

A. could able to

B. could

(答案→)C. was able to

D. ought

解析：be able to 含有“经过努力而完成某一动作”的意思，相当于 manage to do 或 succeed in doing，而 can 只“单纯地表示能力或可能”。