单选题 As the headmaster made a long speech, the ceremony was {{U}}prolonged{{/U}} by ten minutes.
  • A. quickened
  • B. enlarged
  • C. enriched
  • D. lengthened
【正确答案】 D
【答案解析】[解析] 本题考查动词。划线单词prolong的意思是“延长”，与lengthen的含义相近，故本题选D。