IELTS Writing Task 1: How to Describe a Process Diagram for Band 7+
Process diagrams are different from bar charts, line graphs and pie charts because you are usually not comparing numbers. Instead, you are explaining how something is made, produced, developed or changed from one stage to another.
A strong process answer should make the reader feel that they could follow the process from beginning to end without looking at the diagram.
The main idea is:
Identify the stages → understand the overall structure → group the process logically → describe each stage in the correct order → use accurate sequencing and grammar
The biggest mistake students make is simply copying the words written beside each picture. A Band 7+ response should turn those labels into a connected explanation of the whole process.
1. First Understand the Process Before You Write
Do not start writing immediately. Spend a minute analysing the diagram.
First, identify where the process begins and where it ends. Then count the main stages and check whether the process is completely linear or whether it divides into different branches.
For example:
used paper → sorting → shredding → cleaning → pressing → drying → packaging
This is a simple linear process because everything moves in one direction.
A process such as milk production may begin with several common stages and then split:
milk collection → pasteurisation → cooling
then:
yogurt production
and
cheese production
In this type of diagram, your overview should mention that the process divides into two separate production lines.
Some diagrams may also be cyclical, where the final stage leads back to the beginning. Natural processes such as the water cycle are common examples.
Before writing, ask yourself:
How many main stages are there?
Where does the process start?
Where does it finish?
Does it split into branches?
Does anything return to an earlier stage?
Is it a natural process or a manufacturing process?
Which stages can be grouped together?
Once you know these things, the writing becomes much easier.
2. Use a Simple Four-Paragraph Structure
For most process diagrams, a very reliable structure is:
Introduction → Overview → Body Paragraph 1 → Body Paragraph 2
The introduction should usually be one sentence that paraphrases the task.
For example:
The diagram shows how recycled paper is produced.
You could write:
The diagram illustrates the process through which used paper is recycled to produce new paper products.
Or:
The diagram shows how waste paper is converted into recycled paper.
Keep the introduction simple. You do not need to explain any stages yet.
The overview is extremely important because it shows the examiner that you understand the whole process.
A good overview normally tells the reader:
how many broad stages there are;
where the process begins;
where it ends;
whether it is linear or cyclical;
whether it divides into different branches.
For example:
Overall, the process consists of eight main stages, beginning with the collection of used paper and ending with the cutting and packaging of the finished product. Broadly, the procedure involves collecting and sorting the waste material, turning it into clean pulp, and finally producing new sheets of paper.
Notice that the overview does not describe every individual step. It gives the reader the overall structure.
For a process with two outputs:
Overall, the procedure begins with several common stages in which milk is collected, pasteurised and cooled, after which it divides into two separate production lines for yogurt and cheese.
That is exactly the kind of overview a Band 7+ student should aim for.
3. Passive Voice Is Often Essential
In many man-made process diagrams, we care about what happens to the material, not who performs the action. This is why passive voice is extremely common.
Compare:
Workers collect the milk.
with:
The milk is collected.
The second sentence is usually more appropriate because the person doing the action is not important.
Useful passive structures include:
is collected
is transported
is heated
is cooled
is mixed
is filtered
is separated
is crushed
is pressed
is dried
is packaged
is stored
is delivered
is converted into
is added
is removed
For example:
The paper is shredded into small pieces.
Water is added to the mixture.
The liquid is filtered to remove impurities.
The finished product is packaged for sale.
This is particularly useful when the labels on the diagram are just nouns or verbs.
If the diagram says:
Heating
you can turn it into:
The mixture is heated.
If it says:
Water added
you can write:
Water is added to the mixture.
If it says:
Compression
you can write:
The material is compressed into blocks.
That transformation from labels into proper grammatical sentences is a key Task 1 skill.
However, not every process requires passive voice. Natural processes often need active structures.
For example:
The sun heats the water.
Water evaporates.
Clouds form.
Rain falls.
So a useful rule is:
Manufacturing process → passive voice is often dominant.
Natural process → active voice is often more natural.
4. Connect the Stages Instead of Writing a List
A weak process answer often sounds like this:
First, paper is collected. Then it is transported. Then it is sorted. Then it is shredded. Then it is mixed with water. Then it is filtered.
This is grammatically acceptable, but extremely repetitive.
A stronger answer connects stages naturally:
Initially, used paper is collected and transported to a recycling centre, where it is sorted according to type. Once this has been done, the selected material is shredded into small pieces and combined with water to form a pulp. The resulting mixture is then filtered to remove unwanted substances.
Now the process sounds connected rather than like a list.
Useful sequencing language includes:
initially
first
at the first stage
next
following this
after this
subsequently
once this has been done
once X is complete
before
after
before being
after being
at this point
in the next stage
finally
in the final stage
For example:
Initially, the raw material is collected.
Following this, it is transported to a processing plant.
Once the material has been cleaned, it is passed through a machine.
The sheets are dried before being cut into smaller pieces.
In the final stage, the finished products are packaged.
Do not put a linking word at the beginning of every sentence. The goal is natural progression.
5. Group the Process Into Phases
You do not need one sentence for every arrow.
A strong writer often sees larger phases within the process.
Suppose a process has nine stages:
collect paper
transport
sort
shred
mix with water
clean
press
dry
package
You could mentally divide this into three phases:
Phase 1 — Collection and preparation
collection → transport → sorting
Phase 2 — Processing
shredding → mixing → cleaning
Phase 3 — Production of final paper
pressing → drying → packaging
This makes your answer easier to organise.
You might write:
The first three stages concern the collection and preparation of the waste material. Once the paper reaches the recycling centre, it is sorted before being shredded and mixed with water. The latter stages involve removing impurities and transforming the resulting pulp into finished paper.
This is much more sophisticated than describing each picture in isolation.
The same principle works when a process splits.
For the milk diagram:
Common stages: collection → pasteurisation → cooling
Then:
Yogurt: culture → fermentation → pots → chilling → packaging
Cheese: rennet → curds → whey removal → pressing → packaging
The logical structure for the answer is obvious:
Body 1: common stages + yogurt
Body 2: cheese
Or:
Body 1: common preparation
Body 2: compare the two branches
What matters is that the organisation follows the structure of the diagram.
6. Use More Advanced Process Grammar
To reach Band 7+, students should use more than just:
First… then… then… finally…
Several structures are particularly useful.
Once + stage is complete
Once the milk has been cooled, it is divided into two production lines.
Once fermentation is complete, the yogurt is transferred into pots.
After being + past participle
After being sorted, the paper is shredded.
After being cleaned, the pulp is pressed into thin sheets.
This lets you combine two stages smoothly.
Before being + past participle
The paper is dried before being cut and packaged.
Where / during which
The paper is transported to a recycling centre, where it is sorted according to type.
The mixture passes through a cleaning stage, during which ink and other impurities are removed.
Resulting in
The paper is mixed with water, resulting in a thick pulp.
The sheets are dried and rolled, resulting in a continuous length of paper.
Through which
The diagram illustrates the process through which milk is converted into cheese.
After which
The material is pressed into sheets, after which it is dried.
These structures improve grammatical range without making the answer unnatural.
7. Describe Inputs, Transformations and Outputs Clearly
Most processes can be understood in terms of three things:
Input → transformation → output
For example:
paper + water → pulp
You can write:
The shredded paper is combined with water to form a pulp.
Or:
Water is added to the shredded material, producing a pulp-like mixture.
Another example:
milk + rennet → curds
You could write:
Rennet is added to the milk, causing curds to form.
This kind of language helps explain what each stage actually accomplishes.
Useful structures include:
to produce
to form
to create
resulting in
producing
causing
thereby creating
which forms
For Band 7, to produce, resulting in, and causing are more than enough. Do not make every sentence unnecessarily complex.
8. What Should Go in the Overview?
Students often struggle with process overviews because there are no highest or lowest numbers.
For a process diagram, the overview should focus on structure.
Good things to mention include:
number of stages
starting point
finishing point
linear or cyclical nature
major phases
branching
whether human intervention is involved
whether the material changes significantly
For example:
Overall, this is a linear eight-stage process that begins with the collection of used paper and ends with the packaging of newly produced paper.
Or:
Overall, the process involves both natural and human-controlled stages, beginning with bees collecting nectar and concluding with the extraction and bottling of the finished honey.
Or:
Overall, milk initially undergoes the same preparation stages before the process divides into two separate lines, producing yogurt and cheese respectively.
That is much stronger than:
Overall, there are many steps in this process.
9. Do Not Add Information That Is Not Shown
Process diagrams often tempt students to explain things using outside knowledge.
Suppose the diagram shows:
leaves → drying → grinding → packaging
Do not write:
The leaves are dried for several days so that bacteria cannot grow.
Unless the diagram gives that information, you cannot add it.
Similarly:
Honey is filtered because consumers prefer clear honey.
Not shown → do not write it.
IELTS Task 1 requires an objective description of the diagram.
Report only what you can see.
10. Do Not Copy the Labels Word for Word
Suppose the diagram says:
Collect milk
Pasteurisation
Cooling
Culture added
Fermentation
Do not write:
First, collect milk. Then pasteurisation. Then cooling. Then culture added.
You need to convert those labels into academic sentences:
Initially, the milk is collected and pasteurised before being cooled. A bacterial culture is then added, after which the mixture is allowed to ferment.
The diagram gives you information, not finished sentences.
11. Avoid Repeating “Then”
Instead of:
Then it is heated. Then it is cooled. Then it is filtered.
Use sentence structure to show order:
The mixture is initially heated and subsequently cooled. Following this, it is filtered to remove impurities.
Or:
After being heated and cooled, the mixture is passed through a filter.
This is more fluent and shows better grammatical range.
12. Band 6 vs Band 7+ Process Writing
Suppose the diagram shows:
paper shredded → water added → pulp cleaned → sheets pressed
A basic response might say:
First, the paper is shredded. Then water is added. After that, the pulp is cleaned. Then it is pressed.
This is accurate, but limited.
A stronger version would be:
Once the paper has been sorted, it is shredded into small pieces and combined with water to form a pulp. This mixture then undergoes a cleaning stage, during which impurities are removed, before being compressed into thin sheets.
The difference is not difficult vocabulary.
The stronger version:
groups stages;
shows relationships;
uses passive voice accurately;
varies sequencing language;
includes complex grammar naturally.
That is the kind of improvement needed for Band 7+.
Essential Vocabulary for Process Diagrams
Students do not need hundreds of words. They need a flexible set they can apply to many processes.
| Function | Useful language |
|---|---|
| Beginning | initially, at the outset, the process begins with |
| Continuing | next, following this, subsequently, after this |
| Final stage | finally, in the final stage, the process concludes with |
| Adding | add, combine, mix, introduce |
| Removing | remove, filter, separate, drain |
| Changing form | convert, transform, process |
| Breaking | crush, cut, shred, grind |
| Heating | heat, boil, cook, pasteurise |
| Cooling | cool, chill |
| Forming | form, produce, create |
| Moving | transport, transfer, convey |
| Finishing | package, bottle, store, distribute |
| Passive structures | is collected, is heated, is processed, is packaged |
| Result | resulting in, producing, causing, forming |
The important thing is not how many words a student memorises, but whether they can use them accurately and appropriately.
A Reliable Band 7+ Framework
A process answer could follow this general pattern:
Introduction
The diagram illustrates the process through which X is produced.
Overview
Overall, the procedure consists of X main stages, beginning with ___ and ending with ___. Broadly, it can be divided into ___ phases.
Body Paragraph 1
Initially, ___. Once this has been completed, ___. The material is subsequently ___, resulting in ___.
Body Paragraph 2
In the following stages, ___. After being ___, the material is ___. Finally, ___, after which the finished product is ready for ___.
Do not memorise this word for word. Use it as a structural guide.
Final Checklist for a Band 7+ Process Answer
Before finishing, make sure the answer has a clear introduction and overview, follows the stages in the correct order, and does not skip any major part of the process. Check that you have grouped related stages rather than writing one short sentence for every picture.
Make sure the grammar matches the type of process. For a manufacturing process, passive voice will usually be important; for a natural process, active verbs may be more appropriate. Use sequencing language, but avoid beginning every sentence with then. Check that you have not added causes, opinions or technical information that the diagram does not provide.
Most importantly, ask yourself:
Could someone understand the entire process from my writing without seeing the diagram?
If the answer is yes, you are approaching the task correctly.
The key principle is:
Do not merely name the stages. Explain how one stage leads to the next.