单选题 The senior manager, Mr. Valerie, ______ all of the employees filled in their timesheets accurately and submitted them to the payroll division.
  • (A) ensure
  • (B) ensuring
  • (C) ensured
  • (D) to ensure


【正确答案】 C
【答案解析】[结构+语法] 动词位置，时态，数值一致
[错误答案] 现在时也可以，但是由于主语The senior manager是单数，所以要选择单数动词ensures。