25.don’t you think it is time you ------ smoking?

正确答案是B或D.
句子意思：
难道你不认为该是你戒烟的时间了吗?
考点：
虚拟语气.
知识链接：
It's (high/about) time(that ) sb did/should (不能省略)do sth
即,在该结构中,从句要使用【动词过去式；或should+动词原形】结构的虚拟形式,表示与现在事实相反.例如：
It's high time that we learned from each other and worked together.
按照所给选项,两个答案B,D都正确（如果你给的选项准确无误的话）.
祝你开心如意!