8. 8.6.17.1 A Rewrite the sentences using if and unless. 1 Train regularly or else you won't be ready in May. If you don't train regularly, you won't be ready in May./Unless you train regularly, you won't be ready in May. 2 Listen to the coach or you won't know what to do. 3 We'd better hurry or we'll miss the start of the match.
Winter holidays began on 29 December. That day at school was new year's holiday.
We diligently prepared for this holiday. Rehearsed every day until the evening of the dance. In class we had a tea party. We brought a lot of sweet that day. Then we had a disco. I really had a good this last school day before the holidays.
Winter holidays are New year. Met a holiday the whole family. In the evening, pulled a large table and decorated a Christmas tree. In 12 hours we all went outside, where he launched fireworks and lit sparklers.
On other days I'd go out with friends, skating and skiing. Christmas Came. I went to the village to the grandmother and grandfather. There went caroling with his girlfriend. We were given a lot of candy and money.
The holidays have ended, and I still had to do homework, we asked. The weather these days has been great. I love when it's cold and lots of snow.
I really liked these winter holidays.
2. Why do plants and animals require pure water? (Because they cannot survive, if water contains toxic chemicals or harmful microorganisms)
3. What are the major water pollutants? (The major water pollutants are chemical, biological, and physical materials that lessen the water
quality)
4. How can pollutants be separated? (Pollutants can be separated into several different classes.The first class is petroleum products: oil, fuel, lubrication, plastics.The second class is pesticides and herbicides. The third class is heavy metals. The fourth class is fertilizers and other nutrients used to promote plant growth on farms and in gardens. The fifth class is infectious organisms and pathogens. The last one is thermal pollution)
5. How do petroleum products affect the animals? (Many petroleum products are poisonous for animals. Spilled oil damages the feathers of
birds and the fur of animals, often it causes death)
6. Why can pesticides and herbicides be dangerous if they penetrate into streams, rivers and lakes? (When an animal eats a plant that's been treated with it, the poisons are absorbed into the tissues and organs of the animals)
7. What do heavy metals result in? (They can sometimes cause liver and kidney damage)
8. How do fertilizers penetrate to water? (Used to promote plant growth on farms and in gardens)
9. What damage can thermal pollution cause? ( Even a small temperature change in a body of water can drive away the fish and other species that were originally there, and attract other species in place of them. It breaks a balance and can cause serious circumstances in future)