ПОМОГИТЕ ПОЖАЛУЙСТА ​

Ответ:

1. For thousands of years people lived in harmony with environment and it seemed to them that natural riches were unlimited.  

2.Big cities with thousands of smoky industrial enterprises appear all over the world today.

3.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.

4.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

5.Because every human think about future and don't want to die

6.An international environmental research centre has been set up on Lake Baikal.