Band 4.5 IELTS Writing Task 1 Model Answer
Overall Band Score: 4.5 · 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 4.5)
The diagram is showing how the continous cycyling process of biofuel production works, how the the ethanol is produces with the help of natural and non antural processed.
When sunlight combines with carbon dioxie from the air, intrects directly with the plant and trees helps them in growing. Afterwards when these plants are grown and pass though te proess of harvesting, TO extract the useable graisn for the plants we do pre-processing, than cellulose extract from it as an extra material. Cellulose is pass through an chemial processing by which sugar is produced, when the micobeds are added into that sugar Ethanol is Produced. Its used in automobiles and transporation vehicles like trucks, and Airplanes as fual.
Carbon Dioxide generted from the emission of these transoration vehiles and intracts direclt with our environment and open air, in this way that continous cycyling pricess works and helsp in growing the plans again.
AI examiner evaluation
| Criterion | Band |
|---|---|
| Task Achievement / Task Response | 5.0 |
| Coherence and Cohesion | 5.0 |
| Lexical Resource | 4.0 |
| Grammatical Range and Accuracy | 4.0 |
| Overall | 4.5 |
Task Achievement / Task Response — Band 5.0
The student attempts to describe the biofuel production process depicted in the diagram, capturing the general circular nature of the cycle from plants and trees through harvesting, pre-processing, cellulose, processing, sugars, and microbes to ethanol and carbon dioxide emissions. However, the response falls short in several areas. The description contains inaccuracies regarding the sequence and details of the process, such as stating that 'cellulose extract from it as an extra material' and misinterpreting how energy interacts. Furthermore, the overview is weak, and the main features are not fully or clearly reported. The response is just over the 150-word minimum, but the lack of precise reporting and underdeveloped explanation of the process place it within Band 5.0 descriptors.
Coherence and Cohesion — Band 5.0
The essay is divided into three paragraphs, providing some basic structure to the response. However, the logical progression is frequently disrupted by awkward transitions, run-on sentences, and poor referencing (e.g., 'passes though te proess of harvesting, TO extract the useable graisn for the plants we do pre-processing, than cellulose extract from it'). Cohesive devices are either missing or misused, resulting in a mechanical and disjointed flow. Paragraphing is also poorly handled, with the second paragraph being excessively long and containing multiple distinct steps of the diagram clumped together without clear separation. These issues reflect Band 4.5 to 5.0 characteristics, and the score reflects a weak control of overall cohesion.
Lexical Resource — Band 4.0
The vocabulary used is basic and repetitive, with numerous spelling errors throughout the text (e.g., 'continous', 'cycyling', 'antural', 'dioxie', 'intrects', 'te', 'proess', 'graisn', 'than', 'chemial', 'micobeds', 'transporation', 'fual', 'generted', 'helsp'). The student attempts some topic-specific vocabulary such as 'biofuel', 'harvesting', 'cellulose', and 'ethanol', but the high frequency of lexical errors ('non antural processed', 'useable graisn', 'micobeds') noticeably strains the reader and impedes communication in places. This corresponds closely to Band 4.0 lexical descriptors.
Grammatical Range and Accuracy — Band 4.0
The text displays a very limited range of grammatical structures, relying heavily on simple sentences and faulty attempts at complex clauses. There are persistent, major grammatical errors throughout, including missing prepositions, incorrect verb forms ('is showing', 'helps them in growing'), and faulty subject-verb agreement or sentence fragments (e.g., 'When sunlight combines with carbon dioxie from the air, intrects directly with the plant and trees helps them in growing'). Punctuation is also weak, with run-on sentences dominating the response. These frequent errors cause considerable difficulty for the reader and align with Band 4.0 criteria.
See this exact question answered at other band scores — the same prompt compared across bands.
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