The two graphs show the main sources of energy in the USA in the 1980s and the 1990s. Sources of Energy, USA, in the 1980s and 1990s.
Sample Response
The given pie charts show data on the main energy sources in the United States of America in two decades. As is presented in the pie charts, oil was the main energy source for the USA both in the 80s and 90s but the use of oil and coal had reduced and their places as energy sources were somewhat replaced by the use of nuclear power in the USA. According to the given data, oil was the main energy source in the USA which was 42% in 1980. The second-largest energy source in this decade was the natural gas which supplied 26% of total energy in the same period. Then coal supplied more than 20 per cent energy demand in the USA while hydroelectric power and Nuclear power both supplied 5% of the total energy. In the next decade, Nuclear power produced one-tenth of total energy demand and that was almost double that it was in the previous decade. The hydroelectric power as an energy source remained unchanged as it provided 5% of total energy demand in this decade also. The two other main sources of energy in the USA remained almost unchanged in this decade and those two sources were Coal and Natural Gas. Finally, the use of oil as an energy source reduced to 33%, which is almost 10% less than the previous decade but remained the largest source albeit the reduction in this 90s decade.
IELTS Writing Correction
- 1. Chart period Original: in two decades Suggested revision: in 1980 and 1990 Why it matters: The visuals are labelled 1980 and 1990, even though the prompt refers to decades.
- 2. Tense choice Original: had reduced Suggested revision: decreased Why it matters: Use simple past for chart comparisons.
- 3. Awkward phrase Original: their places as energy sources Suggested revision: part of their share Why it matters: This is clearer for pie-chart proportions.
- 4. Article needed Original: supplied 26% of total energy Suggested revision: supplied 26% of the total energy Why it matters: The noun phrase needs the article the.
- 5. Use share language Original: produced one-tenth of total energy demand Suggested revision: accounted for one-tenth of total energy supply Why it matters: The pie charts show shares of sources, not demand production.
- 6. Comparison grammar Original: almost double that it was Suggested revision: almost double what it was Why it matters: This is the correct comparative clause.
- 7. Coal rose Original: remained almost unchanged Suggested revision: changed only slightly for gas but rose for coal Why it matters: Natural gas fell by one point, but coal increased by five points.
- 8. Concise time phrase Original: in this 90s decade Suggested revision: in 1990 Why it matters: The chart label is 1990.
- 9. Percentage points Original: which is almost 10% less Suggested revision: which was 9 percentage points lower Why it matters: For chart shares, percentage points are more precise.
- 10. Phrase form Original: albeit the reduction Suggested revision: despite the reduction Why it matters: Albeit does not fit this noun phrase smoothly.
- 11. Sentence rewrite Original: As is presented in the pie charts, oil was the main energy source for the USA both in the 80s and 90s but the use of oil and coal had reduced and their places as energy sources were somewhat replaced by the use of nuclear power in the USA. Suggested revision: Overall, oil remained the largest source in both years, but its share fell, while coal and nuclear power increased and hydroelectric power was unchanged. Why it matters: The original incorrectly says coal reduced.
- 12. Sentence rewrite Original: The two other main sources of energy in the USA remained almost unchanged in this decade and those two sources were Coal and Natural Gas. Suggested revision: Natural gas changed very little, falling from 26% to 25%, whereas coal rose from 22% to 27%. Why it matters: This gives the precise contrast from the charts.
Suggested Rewrites
- in two decades in 1980 and 1990
- had reduced decreased
- their places as energy sources part of their share
- supplied 26% of total energy supplied 26% of the total energy
- produced one-tenth of total energy demand accounted for one-tenth of total energy supply
- almost double that it was almost double what it was
IELTS Writing Criteria Scores
Detailed feedback by IELTS writing criterion after the annotated essay.
Task Achievement
The response covers all five energy sources and identifies the main trend: oil remained the largest source while nuclear rose and hydro stayed unchanged. Accuracy is weakened by saying coal reduced or that coal and gas were almost unchanged, since coal rose from 22% to 27% and gas only fell slightly.
State the changes source by source: oil fell by 9 percentage points, coal rose by 5, nuclear doubled, gas dipped by 1, and hydro stayed at 5%.
Coherence and Cohesion
The report is logically organized and easy to follow, but the long single paragraph would be clearer if divided into overview and detailed comparison paragraphs.
Use one overview paragraph and one detail paragraph comparing decreases, increases, and unchanged sources.
Lexical Resource
Vocabulary is generally suitable, though a few phrases are wordy or unnatural, such as produced energy demand and this 90s decade.
Use supplied, accounted for, share, fell to, rose to, and remained stable.
Grammatical Range and Accuracy
Grammar is mostly clear, but there are tense, article, and comparative errors, especially around had reduced and double that it was.
Use simple past for chart data and revise comparison phrases such as almost double the previous share.