--- Where is Jack?
--- He _________ football on the playground with those AFS students, but I am not sure.
| A．must be playing | B．must have played |
| C．may be playing | D．may have played |
Finding information in today’s world is easy. The _____ is how you can tell if the information you get is useful or not.
| A．challenge | B．competition |
| C．ability | D．knowledge |
Mrs. White showed her students some old maps _____ from the library.
| A．to borrow | B．to be borrowed |
| C．borrowed | D．borrowing |
The teacher always tells her students that only if _____ hard ____ achieve success.
| A．do they work, will they | B．do they work, they will |
| C．they work, will they | D．they work, they will |
Obviously the measures taken by the local government have _____ the solution to drinking water problems in this region.
| A．contributed to | B．referred to |
| C．turned to | D．devoted to |
Could you drive me to the bookstore at noon if _____?
| A．it's convenient to you | B．you are convenient |
| C．it's convenient of you | D．you will be convenient |