過去に出題されました課題（『Will fossil fuels such as oil and gas still be the world’s main source of energy in the coming decades?』）のサンプル例文です。オンラインのネイティブ講師の確認を受けております。
課題：Will fossil fuels such as oil and gas still be the world’s main source of energy in the coming decades?
Although fossil fuels such as crude oil and coal are economical, due to availability of these resources, environmental impact and the progress of technology, I think alternative forms of energy will replace fossil fuels in the coming decades.
First, scientific research indicates that the reserves of fossil fuels have been declining rapidly in recent years. This has forced energy companies to drill in remote areas like Alaska, but extraction is so difficult and costly that the consumption of renewable energy such as solar power and biomass is progressively increasing, which means renewables will become the world’s primary energy source in the foreseeable future.
Second, conventional fossil fuels contribute to increasing CO2 emissions, which may aggravate(accelerate) the breakdown of ozone layer. However, renewable energy such as wind power and geothermal energy is environmentally friendly. By using these renewables, we can reduce the effects of global warming.
Finally, with advances in science, more and more renewable energy has been developed over recent decades. Public surveys show that nowadays renewable energy accounts for(makes up) about 16% of the world’s energy needs. For instance, Iceland almost completely relies on geothermal energy. In the U.S.,biomass has become the largest source of renewables and currently comprises(provides) nearly 4% of the U.S energy requirement. Additionally, improved batteries are making electric cars more feasible. This signals the demise of the cylinder engine in the coming years.
For the above-mentioned reasons, I am confident that alternative forms of energy will replace fossil fuels and become the most important source of energy in the near future. So, I believe that it is unlikely for the future generations to depend on(turn to) fossil fuels.