Without water, how long can a man ___ out?

I think I turned off the light but I'll go back and _____.

A. be sure
B. make sure
C. feel sure
D. be certain

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甲请朋友乙来家吃饭,乙又领自己的朋友丙一同前来,做饭时甲刚从商店买回不久的高压锅突然爆炸,甲、乙、丙三人均受伤。经查,该高压锅是质量不合格产品,则商店( ) 点击查看答案