Band 6.5 IELTS Writing Task 1 Model Answer

Overall Band Score: 6.5 · Cambridge IELTS 19 · 2026-11-12

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)

Given diagram illustrates how ethanol which is a biofuel is made.

Overall, the process is iterative with around seven steps from the beginning of the process to the end. It starts with the growing plants and ends in a lab where the final product is produced.

It starts with the sunlight reaching the earth and the existing carbon dioxide which helps plants and tress to grow. Machines and tractors are used to harvest these. After harvesting, with the help of pre-processors, we pre-process that harvested plants and tress. The cellulose, we get from pre-processing is then again processed using chemicals and additives to extract the sugar molecules from it.

Once we have the sugar molecules of processed cellulose, microbes are added into it to make ethanol. Ethanol is widely used in cars, trucks and aeroplanes. When the engines of these vehicles combust the ethanol, they emit carbon dioxide which is released into the surrounding environment. The same emitted carbon dioxide helps plants and tress to grow which make this process iterative and an infinite loop of production of ethanol.

AI examiner evaluation

Task Achievement / Task Response: Band 6.5

You cover the main stages and identify the important cyclical feature: plants grow, are harvested and processed into sugars, microbes are added, and ethanol is used by transport before carbon dioxide returns to support plant growth. This gives the reader a clear account of the process. The overview is useful, but it says the process ends “in a lab,” whereas the diagram shows processing in a factory and the cycle continuing back to the plants. Some details are also added without support, such as chemicals and additives being used and engines combusting the ethanol. To strengthen the response, describe the diagram’s stages more precisely and avoid unsupported explanations; also clarify that ethanol is produced after microbes are added, rather than in a lab.

Coherence and Cohesion: Band 6.5

The response has a coherent overall arrangement, with an overview followed by two paragraphs that move through the production stages and then explain the carbon-dioxide cycle. Sequencing phrases such as “After harvesting” and “Once we have the sugar molecules” help the reader follow the process. The final sentence also links the emissions back to plant growth, reinforcing the cycle. However, some connections are repetitive or slightly mechanical, particularly the repeated “It starts” and “After” constructions. The reference in “these” after “plants and tress” is not fully precise, and the shift to “we” makes the description less consistently objective. Use a wider range of concise sequencing and reference devices, and keep each stage clearly linked to the next.

Lexical Resource: Band 6.0

You use an adequate range of process vocabulary, including “harvest,” “pre-process,” “cellulose,” “sugar molecules,” “microbes” and “emit carbon dioxide.” These terms make the stages understandable, and “iterative” shows an attempt to use more precise language. Some choices are inaccurate or unnatural for a process diagram: “a lab” does not match the factory shown, “pre-processors” is not the name of a stage or machine in the diagram, and “infinite loop” is an overstatement. “Plants and tress” also contains a spelling error, while “existing carbon dioxide” is an awkward description. Aim for precise, neutral process language and use the diagram’s labels where possible.

Grammatical Range and Accuracy: Band 6.0

You use a mix of simple and complex sentence forms, including the relative clause in “Ethanol, which is a biofuel” and the time clause beginning “When the engines…”. Most of the process remains understandable despite some grammatical errors. For example, “the cellulose, we get from pre-processing” has an awkward clause structure; write “The cellulose obtained from pre-processing…” instead. In “The same emitted carbon dioxide helps plants and tress to grow which make this process…,” the relative clause has an unclear antecedent and “make” does not agree with the intended subject. There are also inconsistent shifts between passive process description and “we” (“we pre-process,” “we get”). Use passive forms consistently where appropriate and check clause structure and agreement.

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