As soon as his teacher begins lecturing, he begins to doze off, not intentionally but _____.

A．personally

B．randomly

C．habitually

D．unconditionally

在遇到火灾必须穿过浓烟时，应用浸湿的衣物披裹身体，捂着口鼻，快速冲过浓烟。 ( ) 修改：________________________