Band 6.5 IELTS Writing Task 1 Model Answer

Overall Band Score: 6.5 · Cambridge IELTS 19 · 2026-11-13

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 below illustrates the stages that take place during the production of ethanol, ranging from tree and plant growing, which is the longest stage, to harvesting, processing and finally extracting ethanol from the cellulose which is eventually used as biofuel by motor vehicles and planes.

Overall, the plants and trees grow while obtaining sunlight and carbon dioxide from the atmosphere. This step takes place for several years, once they mature, they are harvested and transported to the factory house where they undergo a pre-processing stage.

During this stage, the plants and trees are cleaned, leaving only stems in form of cellulose.

Thereafter, Cellulose is processed and converted to Sugars in form of liquid, Microbes are added and left to ferment. The end product ethanol is eventually produced, which is a biolfuel and used by planes and cars.

While the vehicles and planes are in motion, carbon dioxide is released in the atmosphere and taken up by plants and trees for survival.

AI examiner evaluation

Task Achievement / Task Response: Band 7.0

The response gives a clear account of the main production cycle, including plant growth, harvesting, pre-processing, conversion from cellulose to sugars, the addition of microbes, and ethanol use as fuel. The overview also captures the key circular feature: carbon dioxide released during use is taken up by growing plants. These points address the task well. However, some details are added without support from the diagram, such as growth taking “several years,” cleaning the plants, and microbes being “left to ferment.” The account also omits the truck and does not clearly explain that ethanol is used by three transport types. To strengthen the response, report only visible information and describe the full range of transport shown.

Coherence and Cohesion: Band 6.5

The response is arranged in a sensible sequence, moving from an introductory summary to plant growth, processing, and the return of carbon dioxide. Paragraphing helps distinguish the overview from the later stages, and transitions such as “Thereafter” and “While” make the progression easy to follow. This provides a coherent overall arrangement. However, the first paragraph combines several stages in a long sentence, and the process description is split into short paragraphs in a way that interrupts the flow. The reference in “This step” is also somewhat unclear because it follows a sentence listing several stages. Grouping the stages into two connected body paragraphs and using clearer references would make cohesion more flexible and precise.

Lexical Resource: Band 6.0

The response uses an adequate range of process vocabulary, including “pre-processing,” “cellulose,” “converted,” “microbes,” and “carbon dioxide,” so the stages are generally understandable. It also attempts more specific language such as “undergo” and “end product.” However, some choices are imprecise or unnatural: “factory house” is not an appropriate term for the facility, “in form of liquid” is awkward, and “biolfuel” is misspelled. “Extracting ethanol from the cellulose” also misrepresents the process, since the diagram shows cellulose being processed into sugars before microbes are added. Aim for accurate collocations and consistent technical terms, and avoid adding process details that the diagram does not show.

Grammatical Range and Accuracy: Band 6.0

There is a mix of simple and more complex sentence forms, including the opening participial phrase and the time clause “once they mature.” Most of the meaning remains clear, and the response uses present-tense process descriptions appropriately in several places. Some grammatical errors remain, however. In “This step takes place for several years, once they mature,” the comma joins ideas awkwardly and the reference of “they” is not fully clear. “The plants and trees are cleaned, leaving only stems” also presents a process as a complete passive sequence without clear support, while “carbon dioxide is released in the atmosphere” has an incorrect preposition in the passive construction. Review clause boundaries, pronoun reference, and prepositions, and use a wider range of accurately controlled sentence patterns.

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

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