упр.3. Oil reserves.
Поставьте следующие предложения в вопросительной и отрицательной формах:
- Shale oil and tar sands are the most prevalent form of petroleum.
- Shale oil and tar sands reserves are great.
- The world’s combined proved reserves of crude oil are less than reserves of shale oil.
- Converting of shale oil and tar sands into usable petroleum products is very expensive.
- Relatively little amount of shale oil and tar sands is produced commercially.
- An industry to make oil products from tar sands first started in Canada.
- Oil products produced from shale oil and tar sands will be small in the comming years.
- Total production of conventional crude oil will continue to grow.