________ you have to do the job, you should try your best to do it well even though it may be very difficult for you.
| A．Since | B．While |
| C．Unless | D．Though |
___ in London, the penniless American wandered on the pavement, ___ to find a job to make a living.
| A．Lost; hoped | B．Losing; hoped | C．Lost; hoping | D．Losing; hoping |
---Are you coming to Betty’s wedding?
---I’m not sure. I ______ go to Beijing on business that day.
| A．must | B．would | C．should | D．might |
The children all look forward to _______ the carnival next week.
| A．take part | B．take part in | C．taking part | D．taking part in |
You can trust him because he always ________.
| A．keeps his words | B．stick to his promise |
| C．keeps his word | D．keep his promise |
She speaks English fluently _____ she were a native American.
| A．as though | B．even if | C．as long as | D．ever since |