The diagrams show a structure that is used to generate electricity from wave power.
Sample Response
The diagramscharts illustrate how electricity is produced from the incoming and outgoing wavessea tide and ebb using a structure near the seashore. This structureedifice is a man-made systemtool which produces electricity, thanks to the movement of the sea waves. As can be seen, the process begins with the arrival of athe wave and continues as the wave recedesit finishes when ebb happens. As the first diagram suggests, sea waves enterenter inside the chamber of the structure during the tide and then the incoming wave forces air upwardthe force of the wave permits a powerful movement of the air inside a column in which a turbine is locatedcollocated. Driven by this airflowThanks to the activity of the air, the turbine rotatesstarts to rotate faster and this rotation is used to generate electricity. In the second diagramLooking further in the second diagram, the turbine produces electricity even when the waves move away from the shore as they recededuring the ebb. In fact, when the wave recedeswhen the wave turns back, it creates a reverse flow of airan inverse movement of the air which keeps the turbine turningpermits the movement of the turbine , thereby generating electricitywhich is the source of power for generating electricity.
Why this response received Band 7.0
The response clearly explains how incoming and receding waves move air through the column and drive the turbine, and its sequence is easy to follow. The main content gap is that it never states the turbine turns in the same direction during both phases, while some wording is unnecessarily awkward or repetitive. Prioritise an explicit two-phase overview that highlights this shared turbine direction, then describe each airflow path with more precise technical language.
IELTS Writing Criteria Scores
Task Achievement
The response accurately covers both wave phases and the air-driven generation process, but omits the important fact that the turbine rotates in the same direction throughout.
Make the overview explicit that incoming and outgoing waves reverse the airflow while the turbine continues turning in the same direction to generate electricity.
Coherence and Cohesion
The process is presented in a clear chronological sequence, although the single paragraph and some repetitive linking make the organisation less polished.
Separate the overview from the two process stages and use concise stage links that emphasise the contrast between rising and falling water.
Lexical Resource
A sufficient range of process vocabulary conveys the mechanism clearly, but choices such as 'edifice', 'collocated' and repeated forms of 'movement' sound imprecise.
Use exact diagram terms such as 'chamber', 'airflow', 'column' and 'turbine' consistently, replacing unusual or repetitive wording.
Grammatical Range and Accuracy
The response demonstrates a good range of complex structures with generally clear control, despite occasional awkward constructions and unnecessary relative-clause chaining.
Refine the longest sentences by reducing repeated relative clauses and using direct passive forms to describe each mechanical stage.
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IELTS Academic Writing Task 1
The diagrams show a structure that is used to generate electricity from wave power.
Your response
Write the task yourself, then compare your choices with the annotated response.