The rivers will become dirtier and dirtier ______ we take action to protect them.
| A．since | B．if | C．until | D．unless |
30,000 dollars ______ a large amount of money, but it’s ______ than we need.
| A．is; far more | B．are; more |
| C．is; far less | D．are; less |
Oh, boy, why are you killing your time this way? Can’t you find something ________ doing?
| A．useful | B．cheerful |
| C．enjoyable | D．worth |
His aunt ________ Beijing and she will stay there for three years.
| A．has gone for | B．has been to |
| C．has left | D．has left for |
You ______ to the meeting this afternoon if you have something important to do.
| A．needn’t to come | B．don’t need come |
| C．don’t need coming | D．needn’t come |
---Why don’t we take a little break?
---Didn’t we just have one?
| A．one | B．it | C．this | D．That |