Band 7.0 IELTS Writing Task 1 Model Answer

Overall Band Score: 7.0 · Cambridge IELTS 14 · 2026-09-17

IELTS Writing Task 1 question

The diagram below shows how electricity is generated in a hydroelectric power station.

Summarise the information by selecting and reporting the main features, and make comparisons where relevant.

Student answer (Band 7.0)

The diagram illustrates the process how electricity is generated in a hydroelectric power station.

Overall, the process includes the day-and-night cycle. During the day, river water flows from the high-level reservoir to the low-level reservoir through the reversible turbines, and electricity is generated. At night, the water is pumped back to the high-level reservoir from the low-level reservoir and stored there for reuse on the following day.

River water is stored in a high-level reservoir behind the dam, intake under the dam is opened during the day and water flows from the high-level reservoir through the reversible turbines, before being stored in a low-level reservoir. Water passes through turbines, which in turn power the generator in power station and electricity is generated. Electricity is then transmitted to the National grid via the power lines.

At night, the process changes. Intake beneath the dam is closed at night and low-level reservoir water is pumped back into the high-level reservoir by passing through the same pipe. When the water has been pumped into the high-level reservoir, it can be reused on the following day and the cycle is repeated.

AI examiner evaluation

Task Achievement / Task Response — Band 7.5

The student provides a clear overview of the hydroelectric power station process, successfully capturing both the daytime electricity generation phase and the nighttime water-pumping cycle. Main features such as the high-level and low-level reservoirs, the reversible turbines, the generator, and the connection to the national grid are all accurately reported. The comparison between day and night operations is well-drawn. The response fully satisfies the requirements of Academic Task 1 without any major omissions or misreadings of the diagram.

Coherence and Cohesion — Band 7.0

The response is logically organized with a clear introduction, an overall summary paragraph, and separate body paragraphs detailing the daytime and nighttime operations. Cohesive devices such as 'Overall', 'During the day', 'At night', and 'before being stored' are used appropriately to guide the reader through the cyclical process. Paragraphing is used effectively to separate the two operational modes, ensuring a smooth and logical progression of information throughout the text.

Lexical Resource — Band 6.0

The student demonstrates an adequate to good range of vocabulary appropriate for a process diagram, using terms like 'reservoir', 'reversible turbines', 'generator', 'transmitted', and 'cycle'. There are occasional slight awkwardnesses or minor omissions, such as writing 'the process how electricity' instead of 'the process by which electricity', but overall the vocabulary is precise enough to convey the mechanical steps clearly without impeding communication.

Grammatical Range and Accuracy — Band 6.5

The response features a mix of simple and complex sentence structures, such as 'While water passes through turbines, which in turn power the generator...' and 'When the water has been pumped into the high-level reservoir, it can be reused...'. There are a few minor grammatical slips or punctuation omissions, such as 'intake under the dam is opened' (missing an article) and a comma splice or run-on tendency in places, but the majority of sentences are error-free and do not impede comprehension.

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

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