Though he failed in the experiment again and again he didn’t and at last he made it.A.

问题补充：

Though he failed in the experiment again and again, he didn’t, and at last, he made it.

A. lose his heart

B. lose heart

C. break his heart

D. make up his mind

答案：

A. lose his heart

(答案→)B. lose heart

C. break his heart

D. make up his mind

解析：词义辨析题。A. lose his heart 爱上 B. lose heart灰心 C. break his heart 伤心 D. make up his mind 下决心虽然他的实验一次次失败但是他没有灰心最终他成功了。根据句意选B