单选题 Her dusky arched eyebows {{U}}were knitting and not be frowning,{{/U}} her speaking eyes held both merriment and sorrow, her very frailty had charm.
  • A. are knitting and yet not to be frowning
  • B. were knitted and not yet frowned
  • C. are to be knitted and not yet to be frowned
  • D. were knitted and yet not frowning
【正确答案】 D
【答案解析】该句的knit和frown的主语都是eyebows：knit只能用作过去分词，而frown是eyebows所发出的动作，故应以ing的形式出现。