Itmaybenecessarytostop 国语站 题库 4.95K 大中小设置文本大小 问题详情: It may be necessary to stop__in the learning process and go back to the difficult points in the lessons. A. at intervals B. at random C. at ease D. at length【回答】C知识点:词组 短语题型:选择题 TAG标签:#