Band 6.5 IELTS Writing Task 1 Model Answer

Overall Band Score: 6.5 · Cambridge IELTS 14 · 2026-10-20

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 6.5)

The diagram displays information about the generation of electricity through hydroelectric power station.

Overall, it is a reversible process which means during day time, water moves from high-level reservoir to the low-level reservoir to generate power. However, it moves in the opposite direction during night time.

During the day, the intake is open, causing the water to move from river to the dam, where it flows in the downward direction towards the low-level reservoir. Next, the reversible turbines operate generator which are connected to the reservoir to generate electricity. Then, the electric power move towards the power lines which are interconnected to make a national grid that delivers electricity from power station to the whole city.

On the other hand, during the night, the reversible turbines pump water from low-level reservoir to high-level reservoir. During pumping, water flows in the upward direction to the river and the intake is closed during night.

AI examiner evaluation

Task Achievement / Task Response: Band 6.5

You identify the diagram as a reversible process and clearly contrast the daytime flow with the nighttime pumping cycle, which captures its central feature. You also mention the intake’s different status by day and night, the turbines, generator and national grid. Some details, however, are unclear or inaccurate: during the day, water flows from the high-level reservoir through the intake and turbines to the low-level reservoir, rather than “from river to the dam”; at night it is pumped back to the high-level reservoir, not “to the river.” The claim that the grid delivers electricity “to the whole city” is not shown. To strengthen the response, describe the stages and destinations precisely and avoid adding unsupported information.

Coherence and Cohesion: Band 6.5

The response has a clear overall arrangement: an introduction and overview are followed by separate descriptions of daytime and nighttime operation. Transitions such as “During the day,” “Next,” and “On the other hand” help readers follow the sequence. The progression is generally coherent, but some links between stages are imprecise: “where it flows” follows the reference to the dam, while the water actually passes through the intake and conduit to the turbines. The sentence about power lines and the national grid also adds an unsupported destination, interrupting the process description. Use more precise references and connect each stage in the order shown; this would make the cohesion less dependent on basic sequencing phrases.

Lexical Resource: Band 6.5

You use an adequate range of process vocabulary, including “high-level reservoir,” “reversible turbines,” “intake,” “generator,” and “national grid.” Terms such as “downward direction” and “opposite direction” help describe the two operating modes. Some word choices and collocations are less natural or precise, however: “generation of electricity through hydroelectric power station” would be better expressed as “electricity generation at a hydroelectric power station,” and “operate generator” is not idiomatic. “Electric power move” also has an inaccurate form and sounds awkward. Aim for concise process language such as “water flows through the turbines” and “the generator produces electricity”; this will improve precision while retaining the useful technical vocabulary already present.

Grammatical Range and Accuracy: Band 6.5

You use a mix of simple and complex forms, including the overview contrast “which means…” and the subordinate clause “causing the water to move…”. The day/night contrast is also expressed clearly in several sentences. Some grammatical errors remain, though meaning is generally recoverable. For example, “the reversible turbines operate generator which are connected” has article, agreement and clause-structure problems; “the electric power move” has subject–verb disagreement; and “during day time” needs an article or a more natural time expression. Review articles and agreement, and make sure relative clauses clearly refer to the intended noun. More consistently accurate complex sentences would strengthen the response.

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