题目

用显微镜观察时，欲使物像向右上方移动，应向（   ）移动玻片标本。 A.右上方          B.左上方      C.右下方          D.左下方 答案：A（北京市朝阳区2016届高三第二次（5月）综合练习）Social and cultural activities for senior citizens ______ over the past several years.A. conducted B. were conductedC. have conducted D. have been conducted