题干

The time and effort he has devoted during the past few years ______ trees in that remote area is now considered to be of great value.
A.plantB.plantingC.to plantD.to planting
上一题 下一题 0.85难度 单项选择 更新时间:2011-10-27 12:20:23

答案(点此获取答案解析)