IETLS task 1 - Line graph - Xin góp ý từ các bạn

Question

The line graph compares the total amount of renewable energy spent and main energy sources between 1949 and 2008.

Overall, it can be seen that energy mainly come from wood and hydroelectric power. Wind and biofuels, however, has also contributed to the significant growth in the total consumption of energy since the 2000s.

In 1949, power from both hydroelectric power and wood stood at around 1.5 quadrillion BTU. Over the next 25 years, however, the former steadily rose, reaching 3 quadrillion BTU, while the latter remain almost unchanged. The next three decades experienced a wild fluctuation in both sources of energy. Although there was a considerable increase in the consumption of energy from wood, which slightly exceeded that of hydroelectric power in 1988, hydroelectric power still remain the most used source of energy through the period.

The early 80s marked the advent of biofuel and wind power, although their consumption stayed at a modest level until the beginning of the next century. They then increased sharply, resulting in a spectacular growth in the total amount of consumed energy in 2008.  

Answer 1

The next three decades experienced a wild fluctuation in both sources of energy

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The next three decades both of these types of energy experienced a wild fluctuation.