—I have a headache.
—I’m not surprised you ________ in front of the computer for too long.
| A．work | B．are working | C．have been working | D．had worked |
Our school has an absolute _______ over others, for we have the most hardworking teachers and students.
| A．profit | B．benefit | C．advantage | D．effect |
So suddenly ________that the animals in the zoo looked very frightened during the total solar eclipse (日全食)．
| A．did the sky turn dark | B．the sky did turn dark |
| C．turned the sky dark | D．was the sky turned dark |
Today，we’ll discuss a number of cases ________ parents have much difficulty in communicating with their children.
| A．which | B．as | C．why | D．where |
Chinese smartphone maker Xiaomi Corp said____ it sold 18.7 million smartphones in 2013, up 160 percent year-on-year, and _____ it officially expanded to Singapore ____Jan 1, in a bid to enter the global market.
| A．that, that, in | B．不填, 不填, on |
| C．that, 不填, in | D．不填, that ,on |
China's icebreaker Xuelong ______ by heavy floes since Friday after rescuing passengers on a Russian vessel stranded in Antarctica.
| A．has been trapped | B．had been trapped |
| C．has trapped | D．was trapped |