We work together to achieve our common purpose: _________ world that is safer, cleaner and healthier than __________ one we are living in.
| A．the , / | B．a , / |
| C．the , the | D．a , the |
I'll go to visit my aunt in England ________ the summer holidays start.
| A．while | B．since | C．until | D．as soon as |
--- Have you ever been to Paris, one of ________ cities in Europe?
--- No. But one day I might go there on vacation.
| A．the pleasant | B．the most excited |
| C．more wonderful | D．the liveliest |
What ______ you ______ when the telephone rang just now？
| A．are；doing | B．were；doing |
| C．do；do | D．do；doing |
--- Could you please clean the room?
--- _____ I have to do my homework.
| A．Yes, sure. | B．Why not? |
| C．Sorry, you can’t. | D．Sorry, I can’t. |
--- I feel really tired.
--- ________
| A．Lucky you! |
| B．You'd better work harder. |
| C．Congratulations! |
| D．Why not go and have a rest? |