Band 4.5 IELTS Writing Task 1 Model Answer
Overall Band Score: 4.5 · Cambridge IELTS 19 · 2026-09-14
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 diagram demonstrates the production of biofuel usually known as biofuel.
In overall, it is a cyclic chain contain several stages starting from sustainable energy following by harvesting , pre processing and processing to form sugars along with it microbs are added to produce ethanol for transportation.
To begin with, energy which is present in enviorment such as solar energy from sun and carbon dioxide from plants and tress as well as from combustion of vehicles fuel. Next to it, harvesting of these trees and other vagetations are done for pre prossessing in order to get cellolose as a by product. Then, this cellulose uses in processing to make specific sugars , some microbes which usually react with them are mixed with it to form ethanol.
Eventally, this ethanol is again delivered to cars , buses , trains and plains and this cycle is so on.
AI examiner evaluation
| Criterion | Band |
|---|---|
| Task Achievement / Task Response | 5.0 |
| Coherence and Cohesion | 4.0 |
| Lexical Resource | 4.0 |
| Grammatical Range and Accuracy | 4.0 |
| Overall | 4.5 |
Task Achievement / Task Response — Band 5.0
The student attempts to summarise the diagram showing the production of ethanol, identifying several key stages such as harvesting, preprocessing, processing, and the addition of microbes. However, there are significant omissions and inaccuracies in reporting the main features. For instance, the text claims that 'carbon dioxide from plants and tress as well as from combustion of vehicles fuel' is part of the initial energy source, which misrepresents the diagram's depiction of solar energy and atmospheric carbon. Furthermore, the word count is 148 words, failing to meet the minimum 150-word requirement, which results in a penalty under Task Achievement. Because of the under-length issue and inaccurate reporting of some stages, the response is awarded a band score of 5.0.
Coherence and Cohesion — Band 4.0
The text is organized into short paragraphs, attempting to follow a chronological sequence from the beginning to the end of the cycle. However, the overall progression is hampered by extremely poor punctuation, run-on sentences, and ineffective transitions. Phrases like 'In overall' and 'Eventally' are misused or misspelled. Cohesive devices are used mechanically and often inaccurately, such as 'Next to it' and 'Then, this cellulose uses in processing'. Paragraphing is rudimentary, with the main body compressed into a single dense paragraph that lacks clear internal signposting for the distinct steps of the manufacturing process. This corresponds to a band score of 4.0.
Lexical Resource — Band 4.0
The student demonstrates a very limited vocabulary range, frequently repeating words such as 'biofuel', 'ethanol', 'process', and 'cellulose'. There are numerous spelling mistakes ('enviorment', 'vagetations', 'prossessing', 'cellolose', 'microbs', 'Eventally', 'plains') and severe word-choice errors, such as using 'plains' instead of 'planes' and 'contain' instead of 'containing'. Collocations are unnatural throughout, for example, 'cyclic chain contain several stages'. While the vocabulary is minimally adequate to convey a vague idea of the process, the high frequency of spelling and lexical errors restricts the score to a band 4.0.
Grammatical Range and Accuracy — Band 4.0
The grammatical range is extremely limited, relying heavily on basic sentence structures that are frequently marred by foundational errors. The student struggles with basic subject-verb agreement and voice, as seen in 'harvesting of these trees and other vagetations are done' and 'this cellulose uses in processing'. Sentences are often fragments or run-on structures lacking proper punctuation. There is a complete lack of complex structures used accurately. Frequent grammatical errors cause continuous strain and difficulty for the reader, aligning with the descriptors for a band score of 4.0.
See this exact question answered at other band scores — the same prompt compared across bands.
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