The environment will be further polluted unless some measures _____.
| A．are taken | B．will be taken |
| C．are being taken | D．should be taken |
______ to get a ticket for the concert Eason's Life, George has been standing in a queue for 3 hours.
| A．Determining | B．To determine | C．Being determined | D．Determined |
With the development of high technology, more and more new things ______ in the past years.
| A．discovered | B．have discovered |
| C．had been discovered | D．have been discovered |
That e-book is no larger than an ordinary book with a screen ______ you can read original book and film reviews.
| A．in which | B．of which | C．that | D．where |
It was very lucky to see the "Monster of Lake Tianchi", ______ we didn't see it clearly.
| A．still | B．however | C．now that | D．though |
– Where are you working now?
– In Chongqing. But I _____ in Shanghai for 5 years.
| A．worked | B．had worked | C．have worked | D．had been working |