How the big forest fire has ________ remains to be a mystery.
| A．broken up | B．broken out | C．cut down | D．turned up |
There is no doubt ______ man will conquer nature some day.
| A．whether | B．if | C．which | D．that |
______ different life today is from ____ it was 20 years ago.
| A．What a , what | B．How , what | C．What, what | D．What a , how |
Paper-making began in China and from here it ________ to North Africa and Europe.
| A．spread | B．grow | C．carried | D．developed |
In______1860s, the Italian archaeologist Giuseppe Fiorelli was made______director of the Pompeii dig.
| A．the; 不填 | B．the; the | C．不填; 不填 | D．不填; the |
He worked hard and achieved what he set out to do, but ________ what he had owned, including his health and his marriage.
| A．at the mercy of | B．at the service of |
| C．at the cost of | D．at the risk of |