Question

The energy stored in coal and petroleum originally came to the earth from the sun. The bulk of the present-day supplies was laid down some 200 to 600 million years ago, when tropical conditions were widespread. Lush, swampy forests produced huge trees; warm coastal seas swarmed with microscopic forms of life. When these organisms died, much of their tissue was recycled as it is today — through scavenging and decay. But a significant amount of dead plant and animal material was covered with mud, which prevented complete decomposition. With the passage of time, layer upon layer of the fine sediment was deposited over the once-living material; the sheer weight turned the sediments to rock. Sandwiched between the layers, both coal and petroleum were produced and preserved under pressure. Coal was formed mostly of giant fern-like plants that have only small counterparts today. Coal may still be forming here and there on earth, but conditions are not right for the production of significant quantities.

Write down points without fully expanding verbs, numbering them as you do.

Answer 1

1. Energy stored in coal, petroleum came from sun
2. bulk of present-day supplies – laid down some 200-600 million years ago
3. coastal seas teemed with microscopic forms of life in tropical conditions – these organisms died – tissues recycled through scavenging and decay
4. dead plants and animals covered with mud, prevented from total decomposition
5. layers of sediments- weight accumulation – sediments turned into rocks – pressure built – formation of coal and petroleum preserved under pressure
6. today, conditions unsuitable for coal – production not in significant quantities