Since ancient times Nature has served Man, being the source of his life. For thousands of years people lived in harmony with environment and it seemed to them that natural riches were unlimited. But with the development of civilization man's interference in nature began to increase.
Large cities with thousands of smoky industrial enterprises appear all over the world today. The by-products of their activity pollute the air we breathe, the water we drink, the land we grow grain and vegetables on.
Every year world industry pollutes the atmosphere with about 1000 million tons of dust and other harmful substances. Many cities suffer from smog. Vast forests are cut and burn in fire. Their disappearance upsets the oxygen balance. As a result some rare species of animals, birds, fish and plants disappear forever, a number of rivers and lakes dry up.
The pollution of air and the world's ocean, destruction of the ozone layer is the result of man's careless interaction with nature, a sign of the ecological crises.
c. Did the scientists solve two important problems last year?
Johny asked if he could go for a walk with his friends.
Mr.Longer asked me if i could lend him some money.
My parents asked me if I was hungry.
My little brother asked me if I finished my homework.
I asked the secretary if she was busy.
She asked me if I went to school.
He carried his granny's heavy bag in order not to allow her to carry such heavy things.
1) Nancy <span>will be asked</span><span><span> by the mother </span>to take toys.
2) They are </span>often taken by <span>Nancy to the garden.
3) Winnie came to Nancy. She was called by </span><span><span>Nancy to come</span> into the garden.
4) The book will be interesting. It will be read by Winnie.
5) Nancy's hands were dirty. They were washed by her.
6) Winnie has clean hands. She will be given a cake.</span>
