Band 6.5 IELTS Writing Task 1 Model Answer

Overall Band Score: 6.5 · Cambridge IELTS 19 · 2026-10-15

IELTS Writing Task 1 question

 

The diagram below shows how a biofuel called ethanol is produced.

Summarise the information by selecting and reporting the main features, and make comparisons where relevant.

Student answer (Band 6.5)

The diagram labels the process of production of a biofuel named ethanol.

Overall, it is a cyclic process relying heavily on chemicals and machinery. Carbon dioxide is a natural gas, important in early phase of the process and also released artificially in the end of the process.

The process commences with plants and trees obtaining sunlight and carbon dioxide naturally to grow, followed by harvesting. The harvested plants and trees are pre-processed to obtain a product called cellulose, which is then further processed using chemicals to produce sugars.

Lastly, the addition of microbes in sugars gives the final product in the form of ethanol. The ethanol is used to fuel various kinds of vehicles from cars running on road to airplanes flying in air. All of these transporting vehicles release carbon dioxide into atmosphere. The carbon dioxide is then used again by plants as a source of energyy to grow.

AI examiner evaluation

Task Achievement / Task Response: Band 7.0

The response covers the main stages accurately, from plant growth and harvesting through cellulose, sugars, microbes and ethanol, and it identifies the cycle as the key overall feature. It also reports the use of ethanol in transport and the return of carbon dioxide to plants, so the account addresses the diagram rather than merely listing production steps. Some details are less precise: “relying heavily on chemicals and machinery” is not clearly supported by the labels, and the diagram shows sunlight and carbon dioxide as inputs to plant growth, rather than carbon dioxide itself being a source of energy. The description of carbon dioxide as released “artificially” is also an over-generalisation. A more exact account of the inputs and emissions would strengthen the overview and detail.

Coherence and Cohesion: Band 7.0

The information is organised in a clear sequence: an introductory sentence and overview are followed by the growth and processing stages, then the final fuel use and carbon cycle. Connectors such as “Overall,” “followed by,” “Lastly,” and “then” help the reader follow the process, and the progression is logical throughout. The final paragraph also links transport emissions back to plant growth, making the cycle easy to understand. To make the cohesion more polished, avoid relying mainly on chronological markers and use a few precise references to connect stages—for example, “this material” for cellulose or “the resulting fuel” for ethanol. The overview’s broad claim about chemicals and machinery also interrupts the otherwise focused progression slightly.

Lexical Resource: Band 6.0

The vocabulary is adequate for describing the process, with relevant terms such as “pre-processed,” “cellulose,” “microbes,” and “ethanol.” The writer also uses some variation in describing the stages and transport. However, several choices are imprecise or unnatural: “natural gas” is not an appropriate description of carbon dioxide here, “gives the final product” is informal, and “transporting vehicles” is an awkward collocation. “Energyy” is a spelling error, while phrases such as “running on road” and “flying in air” are not idiomatic. These do not prevent understanding, but greater precision and more natural process vocabulary are needed for stronger lexical control.

Grammatical Range and Accuracy: Band 6.5

The response uses a mix of simple and complex structures, including the passive forms “are pre-processed” and “is then further processed,” as well as a relative clause in “which is then further processed.” Most sentences communicate the sequence clearly, and the final sentence successfully links the emissions to plant growth. Some grammatical inaccuracies remain. In “The process commences with plants and trees obtaining sunlight and carbon dioxide naturally to grow,” the construction is awkward and the relationship between the inputs and growth is unclear. “The addition of microbes in sugars” also uses an incorrect preposition within the phrase. The sentence about vehicles would be clearer with a more direct grammatical structure. More consistently controlled phrasing would build on the range already demonstrated.

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