一个绕地球做匀速圆周运动的人造地球卫星,它的轨道半径增加到原来的2倍后,仍做匀速圆周运动,则( )
( ) In ________ time, those mountains will be covered with trees, too.
( ) This is ________ room. The twin sisters like it very much.
( ) —How’s Joy’s skirt? —Her skirt is more beautiful than ________.
( ) These are ________ and ________ a rooms.
( ) This is ________ and ________ a room.