How can you possibly miss the news? It _______ on TV all day long.
| A．has been | B．had been |
| C．was | D．will be |
The Chinese mainland has 157 billionaires as of 2013，_________second in the number of billionaires worldwide．
| A．having ranked | B．ranked | C．to rank | D．ranking |
Tigers in the state often compete with villagers living close to the reserves for resources, often________ direct conflict．
| A．leading to | B．relying on | C．standing for | D．consisting of |
Before selecting the curtain for your newly-decorated house，it’s important to know what colors look great _______ the wall paper．
| A．on | B．with | C．against | D．in |
___________you try to do something beyond what you have already mastered, you will never grow.
| A．Since | B．When | C．Though | D．Unless |
The smog arrived in the Yangtze River Delta region on Nov．30，_________the air quality in 1 2 cities out of 25 was rated as severely polluted by Dec．1．
| A．where | B．when | C．which | D．what |