单选题 At first, the speaker was referring to the problem of pollution in the country, but halfway in her speech, she suddenly ______ to another subject.
  • A. committed
  • B. switched
  • C. favoured
  • D. transferred


【正确答案】 B
【答案解析】本题测试动词辨异。A．commit犯(错误，罪行)，干(坏事，傻事)；B．switch转换或改变(话题，议题)，意同change；C．favour喜爱，支持；有利于，偏爱；O．transfer迁移，转移。