By the time he realizes he ______ into a trap, it’ll be too late for him to do anything about it.
| A．walks | B．walked | C．has walked | D．had walked |
So difficult __________ it to adapt to the academic requirements of a Western university that I determined to take a preparation course.
| A．I have felt | B．have I felt | C．did I feel | D．I did feel |
.____ you prefer, I’ll give it to you. But we haven’t any other models for you to choose from.
| A．Whatever | B．Whenever | C．Whichever | D．However |
__________in the newspaper last week, the news of his wedding spread quickly in the city.
| A．Having been announced | B．To announce |
| C．Being announced | D．To be announced |
. We must be______that this year might be the worst in recent times for our economic development.
| A．sensitive | B．aware | C．serious | D．bound |
---- What do you think of ______opening ceremony of the 2010Shanghai.World Expo?
---- Oh, it is______perfect one.
| A．the, the | B．an, a | C．the, a | D．an, the |