Take a taxi , _____ you'll miss your train .
| A．and | B．if | C．otherwise | D．or |
I ______ along the road when I saw Peter. So we stopped and had a chat.
| A．walked | B．was walking | C．would walk | D．had walked |
Betty will ring me up as soon as she ______ in Beijing.
| A．arrive | B．arrives | C．arrived | D．will arrive |
The teacher requested that we ______ the classroom after using it.
| A．cleaned | B．cleaning | C．to clean | D．clean |
The moment I met you, I ______ you though I hadn’t seen you for about ten years.
| A．saw | B．recognized | C．knew | D．watched |
No one can imagine the difficulty he had ______ playing computer games.
| A．to give in | B．to give up | C．giving up | D．giving in |