Present Perfect, Past Simple, Past Continuous или Past Perfect. 1. They (told) me yesterday that you (had got) an excellent mark. 2. When did you (receive) a letter from your friend? 3. Our grandmother (was cooking) dinner from twelve till three yesterday. 4. Look! What beautiful flowers she (is buying)! 5. They ( travelled) along the coast of Africa last year. 6. We (have not seen) each other for ages. 7. They (have eaten) all the apples which I (brought). 8. When the children (had had) dinner, they (went) for a walk. 9. Last summer we ( lived) in the country and (went) to the river every day. 10. My sister ( spent) a lot of money yesterday. 11. She is so upset: she (has lost) the key to the front door. 12. By the 1st of September all the children (had returned) from the country. 13. Columbus ( discovered) America 500 years ago. 14. Columbus (did not know) that he (had discovered) America. 15. I have already ( read) five English books. 16. He (had discussed) the problem with a lot of people before he (took) a decision. 17. Mother (has baked) a delicious cake! Sit down at the table and let's eat it! 18. She (was reading) an English book the whole evening yesterday. 19. I have never ( been) to Greece. 20. Have you ever ( been) to the Niagara Falls? 21. At this time yesterday they (were sitting) on the sofa and (listening) to their grandmother who (was telling) them fairy-tales. 22. My friend has just ( rung) me up from London. 23. I (was standing) at the tram-stop when it ( began) raining. 24. We (have not skated) since last winter.
Many wildlife habitats will be destroyed if man keeps polluting the environment. 2. If we dump all sorts of chemicals into rivers, we will not be able to swim in them in the future. 3. If we do not stop cutting down so many trees, we will endanger our oxygen supply. 4. Soon the Earth’s resources will be exhausted if the human population continues to grow. 5. If everybody continues to use aerosols and CFCs, the hole in the ozone layer will get bigger. 6. If the sun radiation can’t escape into space, Earth’s temperature will increase steadily. 7. If the global temperature rises, sea levels will rise too. 8. We’ll threaten our own existence if we do not cut down on waste rapidly. 9. People will run out of drinking water one day if they do not use it more rationally. 10. If he wants to help the planet, then he has to change his habits
2. If we dump all sorts of chemicals into rivers, we will not be able to swim in them in the future.
3. If we do not stop cutting down so many trees, we will endanger our oxygen supply.
4. Soon the Earth’s resources will be exhausted if the human population continues to grow.
5. If everybody continues to use aerosols and CFCs, the hole in the ozone layer will get bigger.
6. If the sun radiation can’t escape into space, Earth’s temperature will increase steadily.
7. If the global temperature rises, sea levels will rise too.
8. We’ll threaten our own existence if we do not cut down on waste rapidly.
9. People will run out of drinking water one day if they do not use it more rationally.
10. If he wants to help the planet, then he has to change his habits