1. If people could prevent all wars, it safer to live in the world. (be)

2. If all weapons disappeared, peaceful citizens . (not die)

3. If I in school competition, I would take the first prize. (participate)

4. If the government didn’t interfered with science, it faster. (develop)

5. If all the people did more to protect our environment, some ecological problems solved. (be)

6. If I had known you needed my advice, I at once. (come)

7. If I you at the cinema, I would have come up to say Hello. (see)

8. If you to your English teacher attentively, you would have done the test correctly. (listen)

1. If people could prevent all wars, it would be safer to live in the world.

2. If all weapons disappeared, peaceful citizens wouldn't die.

3. If I participated in school competition, I would take the first prize.

4. If the government didn’t interfered with science, it would develop faster.

5. If all the people did more to protect our environment, some ecological problems would be solved.

6. If I had known you needed my advice, I would have come at once.

7. If I had seen you at the cinema, I would have come up to say Hello.

8. If you had listened to your English teacher attentively, you would have done the test correctly.