Band 6.5 IELTS Writing Task 1 Model Answer

Overall Band Score: 6.5 · Cambridge IELTS 19 · 2026-09-18

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 illustrates the process of producing ethanol from plants and trees and shows how it forms part of the carbon cycle. First, plants and trees grow by using sunlight and carbon dioxide from the atmosphere. When they are mature, they are harvested and sent for pre-processing, where the plant material is converted into cellulose. The cellulose then undergoes further processing to produce sugars. Microbes are added to these sugars, which helps convert them into ethanol. The ethanol can then be used as a fuel for cars, trucks and aircraft. When these vehicles burn ethanol, they release carbon dioxide into the atmosphere. This carbon dioxide is subsequently absorbed by growing plants during photosynthesis. Overall, the diagram shows a continuous cycle in which plant material is transformed into ethanol and used as fuel, while the released carbon dioxide is reused by plants, making ethanol a renewable biofuel.

AI examiner evaluation

Task Achievement / Task Response — Band 6.0

The student successfully covers all the key stages of the process diagram, from the initial growth of plants using sunlight and carbon dioxide to harvesting, pre-processing, cellulose extraction, processing into sugars, the addition of microbes, and finally the production of ethanol and its subsequent combustion in vehicles. A clear overview is provided at the end, highlighting the cyclical nature of the process and identifying ethanol as a renewable biofuel. However, the response contains 146 words, which falls slightly short of the 150-word minimum requirement. This minor under-length issue prevents a higher band score for this criterion.

Coherence and Cohesion — Band 6.5

The response demonstrates a clear and logical progression throughout. The student effectively uses sequential markers such as 'First', 'When they are mature', 'then', and 'subsequently' to guide the reader smoothly through the various stages of the biofuel production cycle. Paragraphing is handled appropriately, with a concise single-paragraph structure that flows well from introduction of the process to the final conclusion. Referencing is clear, ensuring that pronouns and demonstratives point accurately to the correct entities in the diagram. Cohesive devices are used naturally without being overly mechanical.

Lexical Resource — Band 6.0

The student employs a sufficient range of vocabulary relevant to the diagram, including appropriate terms like 'photosynthesis', 'cellulose', 'microbes', and 'renewable biofuel'. Word choice is generally precise, as seen in phrases such as 'continuous cycle' and 'plant material is transformed'. While the vocabulary is adequate to convey the information clearly, it lacks some of the more sophisticated or uncommon lexical items that would characterise a higher band, remaining somewhat standard throughout the description.

Grammatical Range and Accuracy — Band 7.0

The text displays a good variety of sentence structures, successfully combining simple sentences with complex clauses (e.g., 'When they are mature, they are harvested and sent for pre-processing, where the plant material is converted into cellulose'). Grammatical accuracy is high, with the majority of sentences being error-free and verbs correctly conjugated in the present simple passive tense, which is standard for process descriptions. Punctuation is accurate, and there are no structural errors that impede communication.

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

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