Question

【题目】Over years，scientists have made a great________in the treatment of cancer.

A. breakin B. breakthrough

C. breakup D. breakdown

Answer 1

【答案】B

【解析】考查单词意思辨析。A项“非法进入，闯入”；B项“突破”；C项“破裂”；D项“失败，损坏”。根据句意“在过 去的几年里，科学家在癌症的治疗上已经取得了重大突破”。故答案为B。