IELTS Writing Task 1: Process Diagrams
Process diagrams show how something is made, how something works, or how a natural cycle operates. Unlike graphs and charts, there are no numbers to report — instead, you must describe a sequence of steps clearly and accurately using appropriate grammar and vocabulary.
Process questions appear in around 5-10% of IELTS Academic tests. Candidates who prepare for them often score very well because the structure is predictable and the grammar requirements are clear.
How Process Diagrams Work
There are two main types of process diagram in IELTS:
Examples: The water cycle, the life cycle of a butterfly, how a volcano erupts, the formation of fossil fuels.
Key feature: These are cyclical — the process repeats. There is no human agent performing the actions.
Grammar: Use active voice because natural forces are the agents: "Water evaporates from the ocean surface", "The larvae hatch from the eggs."
Examples: How cement is produced, how chocolate is manufactured, how a newspaper is printed, how glass is recycled.
Key feature: These are linear — they have a clear start and end. Humans or machines perform the actions.
Grammar: Use passive voice because the focus is on the process, not the people: "The raw materials are collected", "The mixture is heated to 1,500 degrees."
Sequencing Language
Because a process is a sequence of steps, you need linking words and phrases that show the order. Here is a comprehensive set organised by position in the sequence.
| Position | Expressions | Example |
|---|---|---|
| Beginning | First, / Firstly, / Initially, / At the first stage, / The process begins when... / To begin with, | Initially, the raw clay is extracted from the ground. |
| Middle (early) | Then, / Next, / After that, / Subsequently, / Following this, / At the next stage, | Following this, the clay is mixed with water to form a paste. |
| Middle (later) | After + noun/gerund, / Once + clause, / When + clause, / The next step involves... | Once the paste has been shaped, it is left to dry in the sun. |
| End | Finally, / Lastly, / In the final stage, / The final step is... / The process ends when... | In the final stage, the finished products are packaged and distributed. |
| Simultaneous | At the same time, / Meanwhile, / During this stage, / While + clause | Meanwhile, the sugar solution is prepared in a separate container. |
Structure Guide
Paragraph 1: Introduction (1-2 sentences)
Paraphrase the question. State what the diagram shows and how many stages there are.
"The diagram illustrates the process by which cement is manufactured, from the extraction of raw materials to the final product. There are five main stages in total."
Paragraph 2: Overview (2-3 sentences)
Provide a summary of the overall process. Mention the number of stages, whether it is linear or cyclical, and what the starting and ending points are.
"Overall, this is a linear manufacturing process that involves extracting, crushing, heating and grinding raw materials. The process requires high temperatures and results in a fine powder ready for use in construction."
Paragraphs 3-4: Body (describe the stages)
Walk through the stages in order. Split them into two paragraphs at a logical break point (e.g., preparation stages vs. production stages). Include specific details from the diagram such as temperatures, equipment names, and what happens at each stage.
Sample Answer 1: Ceramic Pot Manufacturing (Man-Made Process)
The diagram below shows how ceramic pots are produced. Summarise the information by selecting and reporting the main features, and make comparisons where relevant.
Process described: Stage 1: Clay is dug from the ground. Stage 2: Clay is transported to a factory by truck. Stage 3: Clay is mixed with water in a large vat. Stage 4: The wet clay is shaped on a potter's wheel or pressed into moulds. Stage 5: Shaped pots are dried in the open air for 1-2 days. Stage 6: Dried pots are placed in a kiln and fired at 1,000°C for several hours. Stage 7: After cooling, pots are glazed and decorated. Stage 8: Pots are fired a second time at 800°C. Stage 9: Finished pots are inspected, packed and shipped.
The diagram illustrates the nine-stage process involved in the production of ceramic pots, from the initial extraction of clay to the delivery of the finished product.
Overall, this is a linear manufacturing process that can be broadly divided into three phases: preparing the raw material, shaping and drying the pots, and finishing them through two separate firings. The entire process involves both manual labour and industrial equipment.
At the first stage, clay is dug from the ground and transported to a factory by truck. Once it arrives, the clay is mixed with water in a large vat to create a workable paste. This paste is then either shaped on a potter's wheel by hand or pressed into standardised moulds. Following the shaping stage, the pots are left to dry in the open air for one to two days.
After the pots have dried sufficiently, they are placed in a kiln and fired at a temperature of 1,000 degrees Celsius for several hours. Once they have cooled, the pots are glazed and decorated before being fired a second time at a lower temperature of 800 degrees. In the final stage, the completed ceramic pots are carefully inspected for defects, packed into boxes and shipped to retailers.
Word count: 195 words
Sample Answer 2: The Water Cycle (Natural Process)
The diagram below shows the water cycle. Summarise the information by selecting and reporting the main features, and make comparisons where relevant.
Process described: Water in oceans, lakes and rivers is heated by the sun and evaporates, forming water vapour. The vapour rises into the atmosphere and cools, condensing into tiny water droplets that form clouds. When clouds become saturated, precipitation occurs as rain, snow or hail. Some precipitation falls directly into water bodies. The rest falls on land, where some is absorbed by soil and vegetation (infiltration) and some flows over the surface as runoff into streams and rivers. Groundwater slowly moves through underground rock layers back to the sea. The water in rivers and streams also returns to the ocean. The cycle then repeats.
The diagram depicts the natural water cycle, showing how water circulates continuously between the Earth's surface and the atmosphere through a series of interconnected stages.
Overall, this is a cyclical natural process driven primarily by solar energy. It involves three key transformations — evaporation, condensation and precipitation — along with the movement of water across and beneath the land surface before it returns to the ocean.
The cycle begins when the sun heats water in oceans, lakes and rivers, causing it to evaporate and rise into the atmosphere as water vapour. As the vapour ascends, it cools and condenses into tiny droplets, which accumulate to form clouds. When the clouds become sufficiently saturated, the water falls back to Earth as precipitation in the form of rain, snow or hail.
Some of this precipitation lands directly in bodies of water such as oceans and lakes. However, a significant proportion falls on land, where it follows two paths. Part of the water is absorbed into the soil through a process known as infiltration, eventually seeping through underground rock layers as groundwater and slowly making its way back to the sea. The remaining water flows over the land surface as runoff, entering streams and rivers that ultimately carry it back to the ocean, where the cycle begins again.
Word count: 205 words