I know he said so at the meeting is true.
| A．what | B．how | C．why | D．that |
With the help of high technology, more and more new substances ______ in the past years.
| A．discovered | B．have discovered |
| C．had been discovered | D．have been discovered |
I got caught in the rain and my suit _______.
| A．has ruined | B．had ruined |
| C．has been ruined | D．had been ruined |
The wet weather will continue tomorrow, when a cold front ______ to arrive.
| A．is expected | B．is expecting | C．expects | D．will be expected |
His sister left home in 1998, and _______since.
| A．had not been heard of | B．has not been heard of |
| C．had not heard of | D．has not heard of |
When I talked with my grandma on the phone, she sounded weak, but by the time we ___ up, her voice had been full of life.
| A．were hanging |
| B．had hung |
| C．hung |
| D．would hang |