正多面体的面数、棱数、顶点数三在之间存在一个奇特的关系，若用F，E，V分别表示正多面体的面数、棱数、顶点数，则有F+V-E=2，现有一个正多面体共有12条棱，6个顶点，则它的面数F等于（ ）
A：6
B：8
C：12
D：20
His parents don't allow him ________ computer games. They think they are bad for his studies.
— Zhou Fang, can you finish your homework better with _______ time?
— I think I can.
____ you ____ the call now?
