Exercise 1. Open the brackets using correct forms of the verbs:

1. Surgeons (extract) teeth that cannot be (treat).

2. The examination of the oral cavity (perform) by the prosthodontist when people want denturues.

3. Bridges, crowns, dentures and artificial teeth (make) of different materials now.

4. Oral therapy (include) such procedures as cleansing and drilling a tooth before filling it in.

5. To have healthy teeth people must (undergo) dental examination once or twice a year.

1. She (has/had been sitting) at the window since 10 o'clock. (оба варианта применимы, т. к. нет привязки ко времени)
2. He will (be training) from 6 till 8 o'clock next Friday.
3. I didn't speak to him because he (was making) expirement.
4. Now they are ( deciding) where to go for the Holyday this summer.
5. By 5 o'clock the device (had been operating) for 3 hours and didn't stop.
6. I'd like to know what (has) happened to him. (оба варианта применимы) 7. By this time tomorrow the train will (have left) 

1. The hostages were rescued (сказуемое в страдательном залоге) without a shot being fired (обстоятельство - при произведении выстрела).
2. I wish my refrigerator would stop making (составное сказуемое - прекратить делать) that terrible noise. You can’t hear anyone speaking.
3. The results received (определение - какие результаты) were of great importance for further work.
4. People living (определение - какие люди) in Japan have some customs different from ours.
We had already had lunch when he came.