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 how ethanol which is a biofuel is generated.

Overall, it is a closed cycle, where sunlight and carbon dioxide is absorbed by plants which are harvested and then pre-processed to the cellulose before getting processed to sugars. Microbes are added in the processed sugars and ethanol is produced which is further used in transportation vehicles that release carbon dioxide again in the atmosphere.

Ethanol production begins with the absorption of energy by plants and trees from the atmosphere. Plants and trees use absorbed sunlight and carbon dioxide to grow. Once these plants and treese are grown, then next step which is harvesting is carried out. Harvested vegetation is further transferred to a pre-processing machine which separates cellulose from the plants or trees.

Once the pre-processing is completed, separated cellulose is further sent to the labs so sugars can be produced from it. After the processing of cellulose, once sugars are formed then microbes are added in it which produces ethanol. This produced ethanol is then further used as a fuel to run aeroplanes, trucks and cars which release carbon dioxide back in the atmosphere and same carbon dioxide helps vegetation to grow.

AI examiner evaluation

Task Achievement / Task Response — Band 6.5

The student successfully covers all parts of the task by describing the main stages of the biofuel production cycle. An effective overview is provided in the second paragraph, identifying the process as a closed cycle that starts with plant growth and ends with carbon dioxide release through transportation. The linear progression from energy absorption, harvesting, pre-processing, cellulose extraction, and processing into sugars to the addition of microbes and creation of ethanol is clearly reported. Key comparisons and relationships, such as the circular nature of carbon dioxide absorption and emission, are well articulated. The response meets all requirements for a Band 7.0 in Task Achievement by providing a clear and accurate summary of the visual data.

Coherence and Cohesion — Band 6.5

The response demonstrates a clear logical organisation and progression from the introduction to the final step of the cycle. Paragraphing is used appropriately to separate the overview from the detailed body description. Cohesive devices such as 'Overall', 'Once these plants', and 'This produced ethanol' are utilised to connect ideas, although there is a slight tendency to rely on repetitive transitional phrases like 'further' and 'once'. Referencing is generally clear, and the overall arrangement guides the reader smoothly through the sequential steps of the diagram.

Lexical Resource — Band 6.0

The student uses an adequate and appropriate range of vocabulary suitable for a process diagram, incorporating terms such as 'absorption', 'harvested', 'pre-processed', 'cellulose', and 'microbes'. Less common lexical items are attempted with reasonable success, though there are minor awkward collocations or word choices, such as 'generated' instead of 'produced', and 'pre-processed to the cellulose'. Spelling is generally accurate, and vocabulary errors do not impede communication, placing the response solidly in the Band 6.0 to 6.5 range.

Grammatical Range and Accuracy — Band 6.0

The response features a mix of simple and complex sentence structures, including relative clauses ('where sunlight and carbon dioxide is absorbed') and passive constructions ('ethanol is produced'). There are some grammatical inaccuracies, such as subject-verb agreement issues ('carbon dioxide is absorbed') and minor redundancy ('treese', 'then next step'). Punctuation is generally sound, and while complex structures sometimes contain minor errors, they do not impede overall comprehension, reflecting a strong Band 6.5 performance.

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