1. Mike was doing his algebra homework at that time. - Was he? He was watching a new film at the local cinema.
2. Mary was having her dance lesson at that time. - Was she? She was walking with Nick to the park.
3. The Stephensons were driving to the campsite. - Were they? They were flying to India.
4. The guests were visiting the National Gallery at that time. - Were they? They were shopping in Oxford Street.
5. The football players were training at that time. - Where they? They were dancing at the disco club.
6. George was practising this English at that time. - Was he? He was playing computer games.
7. My parents were watching a new film at that time. - Were they? They were tidying the garden.
At the present time the significant changes have been occuring and they are not always positive. Ozone layer protects the earth’s surface from the sun's ultraviolet rays, debilitating the organism's ability to withstand the diseases. It is broken by chlorofluorocarbon, utilizing in aerosol production, in the manufacture of materials for the sterilization of medical equipment and etc. The greenhouse effect and acid rains are the result of burning of the fossil fuels, disposable by different sources. Mass cutting down of forests leads to disruption of the process of rotation the oxygen and carbon in the biosphere. Ecological balance is disrupted also by plenty of disposable garbage and water pollution by harmful substances.
Every year a lot of species of plants and animals have been destroying , forest cover has been exterminating, mineral reserves have been decreasing, the world ocean has been becoming depleted. These losses are incommensurable.
The global environmental crisis may turn into a catastrophe for the planet in the future. If mankind doesn’t change the way of consumption the natural resources, there will begin famine, deficit of clean water and outburst natural disasters. The environmental crisis is overcame by means of ecological education of all stratum of the society, creation of effective nature conservation legislation, implementation the good scientific and technical solutions, applying the conservation ecology.
