单选题 — May I go and play football with Dick this afternoon, Dad?
— No, you can't go out ______ your work is being done.
  • A. before
  • B. until
  • C. as
  • D. after


【正确答案】 C
【答案解析】此题很容易错选B。误认为是not…until句型。实际上只要抓住your work is being done．这一提示就找到了答题的关键。