Band 4.5 IELTS Writing Task 1 Model Answer
Overall Band Score: 4.5 · Cambridge IELTS 19 · 2026-08-16
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 4.5)
The given process chart shows the production of biofuel: Firstly, energy which is a composition of sunlight and carbon dioxide whose formula is CO2 through the use of energy plants and tress are grown then in the next step harvesting of crops takes place then pre processing of crops takes place then breakdown and consumption of cellulose takes place after the breakdown of cellulose takes place for the formation of sugars then microbes are added to the ethanol then at last ethanol is used in various vehicles such as plane, truck and cars etc. this process involves 13 steps It is a cyclic process.
AI examiner evaluation
| Criterion | Band |
|---|---|
| Task Achievement / Task Response | 4.0 |
| Coherence and Cohesion | 4.0 |
| Lexical Resource | 5.0 |
| Grammatical Range and Accuracy | 4.0 |
| Overall | 4.5 |
Task Achievement / Task Response — Band 4.0
The response fails to meet the minimum word count requirement of 150 words, which significantly impacts the score. Because the response is only 104 words, the description of the process is underdeveloped. While you have identified the main steps, the lack of detail and the failure to reach the required length mean that the task is only partially addressed. To improve, you must expand on the stages of the process, describe the inputs and outputs more thoroughly, and ensure you provide a comprehensive overview rather than a brief list of steps.
Coherence and Cohesion — Band 4.0
The response is written as a single, long, run-on sentence, which makes it difficult to follow. There is a lack of paragraphing and appropriate punctuation to separate the different stages of the process. While you use some sequencing words like 'firstly' and 'then', the overall structure is mechanical and lacks logical flow. To improve, you should break your writing into clear paragraphs: an introduction, an overview of the main features, and body paragraphs detailing the specific stages of the process. Using a wider variety of cohesive devices will also help improve the flow.
Lexical Resource — Band 5.0
The vocabulary is quite basic and repetitive, relying heavily on the word 'then' to connect ideas. There are also some awkward phrasing choices, such as 'energy which is a composition of sunlight and carbon dioxide'. The terminology related to the process, such as 'breakdown and consumption of cellulose', is accurate, but the overall range is limited. To achieve a higher score, try to use more precise verbs and nouns related to industrial processes, and avoid repeating the same transition words throughout the text.
Grammatical Range and Accuracy — Band 4.0
The response consists of a single, extremely long sentence that lacks proper punctuation, making it grammatically incorrect. There are frequent errors in sentence structure, such as the lack of commas and periods to separate distinct clauses. The use of 'whose formula is CO2' is an unnecessary inclusion that disrupts the flow. To improve, you must focus on writing shorter, clear sentences and using correct punctuation. You should also practice using a mix of simple and complex sentence structures to demonstrate better grammatical control.
See this exact question answered at other band scores — the same prompt compared across bands.
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