Band 6.5 IELTS Writing Task 1 Model Answer

Overall Band Score: 6.5 · Cambridge IELTS 19 · 2026-09-30

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 chart shows the cycle of ethanol production and its consumption. The process describes how the sun’s energy nurtures the plants and trees, and how the chemical processes are used to produce ethanol for fuel purposes.

The first stage is to cultivate plants and trees in farms, then the grown plants and trees are harvested for further processing. Cellulose is produced by doing pre-processing on the crop yield from the plantation.

Further processing on the cellulose creates sugars. When microbes are added to the produced sugars, they form a new substance called ethanol. Then this ethanol is consumed as a fuel in various transportation vehicles such as cars, trucks and aeroplanes. These vehicles burn the ethanol and give off carbon dioxide as a by-product which is released back into the atmosphere. The same carbon dioxide can be used by plants and trees to grow.

Hence, the cycle of the carbon dioxide is completed as it moves from plants and trees to ethanol and is released back to the air from vehicles.

AI examiner evaluation

Task Achievement / Task Response: Band 6.5

The student successfully covers all main features of the diagram, accurately detailing the cyclical process of biofuel (ethanol) production from plants and trees through to harvesting, pre-processing, cellulose creation, processing into sugars, and finally fermentation with microbes. The student also correctly notes the combustion of ethanol in vehicles and the subsequent release of carbon dioxide back into the atmosphere to complete the cycle. The overview provided in the opening paragraphs outlines the scope of the process effectively, and all relevant stages are reported in correct sequence without significant omissions or inaccuracies. Thus, the response earns a solid band 7.0 for addressing all parts of the task clearly and accurately.

Coherence and Cohesion: Band 6.5

The text displays a clear logical organisation and progression from the beginning to the end of the biofuel cycle. Paragraphing is used appropriately, with each stage of the process logically separated into distinct paragraphs (introduction, intermediate steps, consumption/release, and summary). Cohesive devices such as 'then', 'further processing on', and 'hence' are used to connect ideas, though some transitions feel slightly mechanical or repetitive in structure. Referencing is generally clear, allowing the reader to follow the cyclical flow easily, which aligns well with the descriptors for Band 7.

Lexical Resource: Band 6.0

The student demonstrates an adequate and generally appropriate range of vocabulary suitable for describing a process diagram, using terms such as 'cultivate', 'cellulose', 'microbes', and 'by-product'. There are attempts to use less common lexical items related to the scientific process ('fermentation' is absent, but terms like 'pre-processing' and 'combustion' equivalents like 'burn' are used). Word choice is mostly precise, although phrasing can occasionally be slightly simple (e.g., 'the first stage is to cultivate plants and trees in farms'). Spelling and word formation are accurate throughout, allowing for a comfortable reading experience that fits Band 6.5 or 7.0; a band 6.5 is awarded as the vocabulary is somewhat standard rather than consistently sophisticated.

Grammatical Range and Accuracy: Band 6.5

The response exhibits a good mix of simple and complex sentence structures, including relative clauses and conditional-style transitions (e.g., 'When microbes are added to the produced sugars, they form...'). Grammatical accuracy is generally high, with frequent error-free sentences. Minor awkwardness occurs, such as 'Further processing on the cellulose creates sugars', where a more passive or nominalised structure might sound more academic ('Further processing of the cellulose yields sugars'). However, these minor issues do not impede communication at all, demonstrating good overall control of grammar and punctuation that warrants a Band 7.0.

See this exact question answered at other band scores. The same prompt compared across bands.

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