Поставьте к каждому предложению по пять вопросов:
1. Numerous antipollution acts passed in different countries.
2. The environmental problems is caused by industrial pollution.
3. Purifying systems have been installed for treatment of industrial waters.
4. The solution requires the cooperation of all nations.
5. In recent years the pollution problems have received great publicity.
6. Measures have been taken to protect rivers and sees from oil water.