—Areyousureyouhavetodothisnow?It'sbeenverylate．—Idon'tk...

问题详情：

—Are you sure you have to do this now? It's been very late．

—I don't know         to do it if not now．

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

【回答】

D

知识点：相似 相近词比较

题型：选择题