Do you know ___ he did not turn off the light.A.how B.why C.what D.whether
问题描述：
Do you know ___ he did not turn off the light.A.how B.why C.what D.whether
答
填B.why（为什么）
Do you know （why） he did not turn off the light.
翻译；你知道他为什么没有关灯么.
求采!