Every possible means to prevent the air pollution, but the sky is not still clear.
| A．is used | B．are used | C．has been used | D．have been used |
We all sighed with ________ relief when ________ plane finally landed safely.
| A．a; / |
| B．/; the |
| C．a; a |
| D．a; the |
This is our contribution to ________ world of the 21st century, ________ world of independence and mutual understanding.
| A．the; / |
| B．/; a |
| C．a; the |
| D．the; a |
Sarah looked atfinished painting withsatisfaction.
| A．不填；a |
| B．a; the |
| C．the; 不填 |
| D．the; a |
According to some students, ______ listening practice is still ______ must in Senior 3, because it helps promote the sense of language.
| A．the, a |
| B．the, \ |
| C．\, a |
| D．\, an |
This ischallenging job I mentioned to you the other day． Have you had anyone inmind for it now?
| A．a, the |
| B．the;/ |
| C．the, the |
| D．a:/ |