题目

They communicate with each other about their study every night.(对划线部分提问) do they communicate with each other about theirstudy? 答案：【1】How【2】often下列现象与物理知识相对应的是（ ）A．深秋早晨的雾--液化B．磁铁能吸引大头针--分子间存在引力C．灰尘在空中飞舞--分子在永不停息地运动D．冬季人们常用热水袋取暖--做功改变物体内能