—Areyousureyouhaveto?It’sbeenverylate.   —Idon’tknow

问题详情：

—Are you sure you have to ? It’s been very late.  

  — I don’t know_____I can do if not now.

  A. where   B. why    C. when   D.  how

【回答】

C

知识点：连词

题型：选择题