Nowadays，itiscommontoseepeoplestaringattheirmobilephone...
来源：语文精选馆 1.38W
问题详情：
Nowadays，it is common to see people staring at their mobile phones instead of reading a real
book＿＿＿＿＿＿many experts are worried．
A. when B ．for which C ．where D. about which
【回答】
D
知识点：定语从句
题型：选择题
