Раскрыть скобки (use the Past Simple or the Past Continuous or the Past Perfect) 1. He (closed) the window and (sat) in his armchair, reading a newspaper. 2. When I (arrived) the lecture had already (started). 3. The rain (stopped) and the sun (shone) brightly. 4. Unfortunately when I arrived Ann was just (leaving), so we only had time for a few words. 5. I (watched) his eyes pretty closely while we (were exchanging) these remarks. 6. When we (reached) the field, the game had already (started). 7. He suddenly (realized) that he (was travelling) in the wrong direction. 8. When I (was looking) for my passport, I (found) this old photograph. 9. You looked very busy when I saw you last night. What were you (doing)? 10. He (wasn't) there 5 minutes, when the storm (began). 11. He (didn't allow) us to go out in the boat yesterday as a strong wind (was blowing). 12. I (called) Paul at 7.00 but it wasn't necessary because he had already (got) up. 13. When I (heard) his knock I (went) to the door and (opened) it, but I (didn't recognized) him at first because I (wasn't wearing) my glasses. 14. When he (sealed and stamped) the envelope, he (went) back to the window and (drew) a long breath. 15. I (saw) you yesterday from the bus. Why were you (using) a stick? – I (was using) it because I (hurt) my leg that morning. 16. We (returned) home at nightfall and we (were) very glad to get home again, but we (had had) a wonderful day. 17. As they (were walking) along the road they (heard) a car coming from behind them. Tom (turned) round and (held) up his hand. The car (stopped). 18. When I (arrived) at the station Mary (was waiting) for me. She (was wearing) a blue dress and (looked) very pretty. 19. When I (saw) him he (was painting) a portrait of his wife. 20. While he (was watering) the flowers it (began) to rain. 21. While I (was saying) goodbye to the rest of the guests Isabel (took) Sophie aside. 22. The men (said) that they (had been working) on the road outside my house and that they (wanted) some water to make tea.
2. Pollution sewage-water sources undesirable forms of microorganisms and microfauna and solid sediment contributes to decrease the content of oxygen in the water and change in her composition of microorganisms.
3. Soil washout with coastal areas helps to silting of water bodies, especially of the small rivers.
4. Смытая soil, fertilizers and organic sewage contribute to the development of the waters of unusual algae and change of the species composition of ecosystems.
5. The poisoning of the soil and water with toxic substances from the waste of various productions.
6. Changing the PEAK of the soil nearby from dumping areas due to the constant inflow of leachate, saturated with heavy metals, pesticides, dyes, oxides of various elements.
7. Air quality iodine influence of combustion of fuel, garbage, tires, stubble residues that causes acid rain.
8. Contamination of air, soil and water with radioactive substances, the number of which increases every year due to human activity: the production of nuclear energy (nuclear, atomic weapons), waste (slag) from the manufacture of individual elements, the production of radioactive substances (uranium, vanadium, etc.).
9. Increase in the number of gaseous substances (carbon dioxide, dioxides)emitted into the air (emissions of enterprises, in waste incineration etc), lowers the amount of oxygen that contributes to climate change.
10. Pollution of the environment with wastes of human activity is the cause changes in the gene pool of organisms of many ecosystems, including man, enters in food prices increased concentrations of individual substances and compounds (reactive), changing species and population composition of the systems.