Whenyouareplantingtrees,thetrees 国语站 题库 2.36W 大中小设置文字大小 问题详情: When you are planting trees, the trees ________ straight in the hole. A. must put B. must be put C. are putting D. is put【回答】B知识点:动词语态题型:选择题 TAG标签:#