未知题型 Anna was reading a piece of science fiction, 怎么选择

未知题型 This crop has similar qualities to the previous one, _______ both windresistant and adapted to the same type of soil. A) being B) been C) to be D) having been

未知题型 Although they plant trees in this area every year, the tops of some hills are still _______. A) blank B) hollow C) vacant D) bare