北京是全国的________、文化中心，也是________中心。
政治；国际交往
SW-160型转向架的组装顺序及要求是什么？
The newly designed iPhone 5 on the market____________ well now. Get one before it __________out in the shop.
A．sells, is sold
B．sells, sells
C．is sold, is sold
D．is sold, sells
