如图所示,用毛皮摩擦过的橡胶棒接触验电器的金属球时,验电器的两片金属箔之所以张开是由于( )
同种电荷相互排斥
异种电荷相互吸引
同种电荷相互吸引
异种电荷相互排斥
Mom was cooking ________ Dad was reading newspapers.
It’s late. David washes his face _______ goes to bed.
()—Do you believe that paper is made ________ wood? —Yes, I do. And you can see that books are made ________ paper.
Guangdong is ____ the south of China .
I read an article ________ a young writer ________ the UK last week.