第21题: [单项选择]If the whole operation ______ beforehand, a great deal of time and money would have been lost. A. was not planned B. has not been planned C. had not been planned D. were not planned 参考答案:C 答案解析:[考点] 谓语动词。 [解析] 本题测试虚拟语气。表示与过去事实相反的虚拟语气,从句中应使用had+过去分词。