Band 6.5 IELTS Writing Task 1 Model Answer

Overall Band Score: 6.5 · Cambridge IELTS 19 · 2026-08-19

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 production of biofuel and its cycle. The process starts with plants growing and ends with ethanol being used as fuel in vehicles.

Overall, harvesting is a crucial part of this process, whereas processing is an essential stage for converting plants into biofuel.

To begin with, plants grow by using energy from sunlight and carbon dioxide. Once the plants and trees are fully grown, they are harvested using machines such as tractors. Moreover, the harvested materials are passed through machines for pre-processing to extract cellulose from the plants. The cellulose is then processed, and sugars are added to convert it into ethanol. In addition, microbes are added to complete the process of ethanol production. Finally, the ethanol is ready to be used as fuel in various vehicles such as cars and trucks. The carbon dioxide produced by these vehicles is absorbed by plants, which use it during the process of photosynthesis.

AI examiner evaluation

Task Achievement / Task Response — Band 6.0

The response covers the main stages of the process, from plant growth to fuel usage. However, it lacks a clear overview of the cyclical nature of the process, which is a key feature of the diagram. While the steps are described, the response could be improved by highlighting the transformation stages more explicitly rather than just listing them. The description of the 'pre-processing' and 'conversion' stages is accurate, but the response would benefit from more precise terminology regarding the inputs and outputs at each stage to better meet the requirements for a Band 7.

Coherence and Cohesion — Band 6.5

The response is logically organized, moving chronologically through the process. Paragraphing is used effectively to separate the introduction and overview from the detailed description. Cohesive devices such as 'To begin with', 'Moreover', and 'Finally' are used appropriately to guide the reader. However, the transition between the description of the production process and the final stage of the cycle (carbon dioxide absorption) is slightly abrupt. The flow is generally smooth, and the information is presented in a clear, coherent manner throughout the text.

Lexical Resource — Band 6.0

The vocabulary is adequate for the task, with accurate use of technical terms like 'cellulose', 'photosynthesis', and 'microbes'. The range is sufficient to describe the process clearly. However, the language is somewhat repetitive, relying on simple verbs like 'use' and 'add'. To reach a higher band, the student should incorporate more precise verbs related to industrial or chemical processes, such as 'extract', 'ferment', or 'synthesize'. There are no significant spelling errors, and the vocabulary used is appropriate for the context of a process description.

Grammatical Range and Accuracy — Band 6.5

The response demonstrates a good control of grammar with a mix of simple and complex sentence structures. Most sentences are error-free, and punctuation is used correctly. The use of passive voice (e.g., 'are harvested', 'are passed', 'is processed') is appropriate for describing a scientific process. While the grammatical range is solid, it lacks a wider variety of complex structures or more sophisticated subordinating clauses that would elevate the writing to a higher band. Overall, the accuracy is high, and the meaning is never obscured by grammatical slips.

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

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