Put the verbs in brackets into the correct forms.

1. In my country, certain prices (control) ……………………..… by the government, such as the prices of medical supplies. However, other prices (determine) ……………………..… by how much people are willing to pay for a product.

2. The world's first television images (show) ……………………..… to scientists in Scotland in 1926.

3. Although penicillin (invent) ……………………..… By Alexander Fleming, he (not / know) ……………………..… how to make it into a medicine. It first (make) ……………………..… into a medicine ten years later, by an Australian scientist Howard Florey.

4. Mobile phones, digital cameras, flat-screen T.V, DVD players (manufacture) ……………………..… by Samsung.

5. My brother and I (invite) ……………………..… (spend) ……………………..… a few days’ holiday in a cottage in the country last summer. The cottage (have) ……………………..… no comfortable furniture in it, many of the windows (break) ……………………..… and the roof (leak) ……………………..… making the house damp.

6. Radios (use) ……………………..… to broadcast coded messages during the Second World War.

7. Things (change) ……………………..… a great deal at Coltech, Inc. When we first (start) ……………………..… working here three years ago, the company only (have) ……………………..… six employees. Since then, we (expand) ……………………..… to include more than 2000 full-time workers.

8. All the beautiful buildings in our cities (destroy) ……………………..… by exhaust gases from cars now. We must (do) ……………………..… something to stop this.

9. When I first (come) ......................... to this house, it (be) .........................a very quiet area. But since then a new housing estate (build) ……………………..… and it (become) ……………………..… very noisy.

10. Old Ben (sell) ……………………..… newspapers just inside the station entrance, and my father always (buy) ……………………..… his evening paper from him as he (leave) ……………………..… the station on his way home.