IELTS Writing · Ch 05

Task 1 Academic — Process Diagram

Passive voice · sequencing connectors · present simple

Topic & Why It Matters

A process diagram asks you to explain how something is made, recycled, grown, treated, or delivered. The challenge is not finding a trend; it is turning labelled arrows into a clean sequence that the examiner can follow without looking back at the diagram.

Candidates usually lose marks by skipping the overview, mixing tenses, or writing a list of steps with no grouping. A strong process answer uses present simple passive grammar, groups stages into logical phases, and describes only what the diagram shows.

Knowledge Points

A process is about sequence, not comparison
Unlike charts and tables, a process diagram usually has no numbers to compare. Your job is to describe the order of stages clearly, showing where the process begins, how materials change, and where it ends.
Use present simple for undated processes
Most IELTS process diagrams describe a general system rather than a past event. Use present simple passive forms such as 'is collected', 'is heated', and 'is packaged'. Do not use past tense unless the diagram gives a past date.
Passive voice is the default grammar
The actor is often unknown or unimportant in process diagrams. Instead of writing 'workers sort the paper' repeatedly, write 'the paper is sorted'. This keeps the focus on the material and the stages.
The overview names the shape of the process
A strong overview states whether the process is linear, cyclical, natural, or man-made, then identifies the first and final stages. It may also mention a major transformation, such as raw material becoming a finished product.
Group minor steps into phases
If a diagram has eight or more labels, do not give every label equal weight. Group them into two body paragraphs, such as 'preparation stages' and 'manufacturing stages'.
Do not invent missing details
If the diagram does not show temperatures, times, machinery names, or reasons for a step, do not add them. Process answers are marked for accurate description, not technical explanation.

Structure Template

Four paragraphs, about 150-175 words total. Group the stages before writing.

ParagraphTargetWhat to Write
Paragraph 1 — Introduction20–30 wordsParaphrase the prompt. Name the process and the input/output if they are clear.
Paragraph 2 — Overview35–45 wordsState the process shape (linear/cyclical), the first and final stages, and the major transformation. Avoid tiny step details here.
Paragraph 3 — Body A45–60 wordsDescribe the early stages in order. Use passive voice and sequencing language, but avoid starting every sentence with 'then'.
Paragraph 4 — Body B45–60 wordsDescribe the later stages and the final product. End when the diagram ends; do not add future uses unless shown.
The golden rule: Write the overview as a map of the whole process: start point, end point, and main transformation. Save individual steps for the body paragraphs.

Vocabulary & Grammar Toolkit

ExpressionUsage Note
at the first stageA clear opening phrase for the first body paragraph
initially / first / to begin withAlternatives for the beginning of a process
subsequently / afterwardsFormal alternatives to 'then'; use sparingly
once [step] has been completedComplex sequencing: 'Once the paper has been sorted...'
after this / following thisSimple, safe sequencing phrases
before being [past participle]Compact passive sequence: 'before being transported'
is collected / is transportedPassive verbs for movement stages
is sorted / is separatedPassive verbs for selection and removal
is shredded / is crushed / is groundPassive verbs for breaking material down
is mixed withUse when an input combines with water, chemicals, or another material
is heated / is cooledUse only if temperature change is shown
is filtered / is screenedUse when impurities are removed through a barrier or screen
is pressed / is driedUseful for manufacturing processes involving moisture
is converted intoShows transformation from one state/product to another
is passed throughUse for material moving through machines, tanks, rollers, or pipes
raw materialsThe starting inputs, such as waste paper or clay
finished productThe output at the end of a man-made process
impurities / contaminantsUnwanted materials removed during cleaning
the remaining materialCohesive reference that avoids repeating the noun
a linear processA process with one clear start and end point
a cyclical processA process that returns to an earlier stage and repeats
the final stage involves...Useful sentence frame for the last step
where it is...Relative clause for location or stage: 'a tank, where it is cleaned'

Common Pitfalls

MistakeCorrection
Writing no overviewEven without numbers, Task 1 still requires an overview. State the process type, beginning, end, and major transformation.
Using past tense for a general processMost process diagrams need present simple: 'The paper is sorted', not 'The paper was sorted'.
Overusing 'then'Use a mix of sequencing devices: 'At the first stage', 'After this', 'Once the pulp has been cleaned', and passive clauses with 'before being'.
Inventing technical detailsDo not add exact temperatures, durations, brand names, or machinery unless the diagram shows them.
Explaining why the process happensIELTS Task 1 asks what happens, not why. Replace 'This is done to save trees' with a factual stage description.

Practice Prompt

Set a 20-minute timer. Write your response before reading the model answer.

You should spend about 20 minutes on this task.

The diagram below shows how recycled paper is produced from used paper collected from households and offices.

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

Write at least 150 words.

Process stages shown in the diagram:
1Used paper is collected from households and offices.
2The paper is transported to a recycling plant.
3Unsuitable materials are removed during sorting.
4The remaining paper is shredded and mixed with water and chemicals.
5The mixture is screened to remove small impurities.
6Ink and glue are separated from the fibres in a de-inking tank.
7The cleaned pulp is pressed and dried into sheets.
8The finished paper is rolled and prepared for reuse.
My Response
0 / 150 words
150 more words needed

Model AnswerBand 7.5+ · 180 words

The diagram illustrates the stages involved in producing recycled paper from used paper collected from households and offices.

Overall, the process is linear and consists of eight main stages, beginning with the collection and sorting of waste paper and ending with the paper being dried, rolled and prepared for reuse. The key transformation occurs when the paper is converted into pulp and cleaned before being pressed into sheets.

At the first stage, used paper is collected from homes and workplaces before being transported to a recycling plant. It is then sorted manually or mechanically, and unsuitable materials, such as plastic, staples and heavily contaminated paper, are removed. The remaining paper is shredded and mixed with water and chemicals in a pulper.

Next, the mixture is screened to take out small impurities and then cleaned in a de-inking tank, where ink and glue are separated from the fibres. After this, the pulp is spread onto a moving mesh belt, pressed to remove excess water and dried with heated rollers. Finally, the finished paper is wound into rolls and prepared for reuse.

Annotated Commentary

Each paragraph is quoted, then broken down by examiner criteria. Notice how the answer uses passive grammar and sequencing without turning into a bare list.

[ Paraphrase ]Paragraph 1 — Introduction
The diagram illustrates the stages involved in producing recycled paper from used paper collected from households and offices.
Lexical upgrade'stages involved in producing' replaces the simpler phrase 'how to make'
Task framingNames both the input (used paper) and the output (recycled paper)
Syntax change'collected from households and offices' compresses source information into a reduced passive clause
[ Thesis ]Paragraph 2 — Overview
Overall, the process is linear and consists of eight main stages, beginning with the collection and sorting of waste paper and ending with the paper being dried, rolled and prepared for reuse. The key transformation occurs when the paper is converted into pulp and cleaned before being pressed into sheets.
Thesis (overview)States the process shape, starting point, end point, and main transformation
Cohesive device'beginning with...' and 'ending with...' show the full sequence without listing every step
Complex grammar'when the paper is converted into pulp and cleaned before being pressed...' uses passive coordination and a reduced clause
Data selectionNo unnecessary equipment details appear in the overview
[ Topic sentence ]Paragraph 3 — Body A
At the first stage, used paper is collected from homes and workplaces before being transported to a recycling plant. It is then sorted manually or mechanically, and unsuitable materials, such as plastic, staples and heavily contaminated paper, are removed. The remaining paper is shredded and mixed with water and chemicals in a pulper.
Topic sentence'At the first stage' clearly begins the ordered description
Cohesive device'then' and 'The remaining paper' connect the collection, sorting, and pulping stages
Complex grammar'before being transported' and 'such as...' add detail without creating extra short sentences
Passive voice'is collected', 'is sorted', 'are removed', and 'is shredded' keep the focus on the material
Lexical upgrade'unsuitable materials' and 'heavily contaminated paper' are more precise than 'bad things'
[ Contrast ]Paragraph 4 — Body B
Next, the mixture is screened to take out small impurities and then cleaned in a de-inking tank, where ink and glue are separated from the fibres. After this, the pulp is spread onto a moving mesh belt, pressed to remove excess water and dried with heated rollers. Finally, the finished paper is wound into rolls and prepared for reuse.
Topic sentence'Next' signals the move from preparation to cleaning and finishing stages
Cohesive device'After this' and 'Finally' guide the examiner through the last stages
Complex grammar'where ink and glue are separated...' uses a relative clause to describe the de-inking tank
Passive voice'is screened', 'are separated', 'is spread', 'pressed', 'dried', and 'is wound' maintain process style
Task accuracyThe answer stops at the finished paper stage and does not invent future uses

Self-Check

Answer these from memory before looking back. If you cannot answer all, re-read the relevant section.

  1. What tense and voice do most undated process diagrams require?
  2. What three things should a process overview normally identify?
  3. Rewrite this sentence in passive voice: 'Workers sort the used paper and remove plastic.'
Answers: (1) Present simple passive, unless the diagram gives a dated past process. (2) The process shape, the first stage, the final stage, and usually the main transformation. (3) 'The used paper is sorted, and plastic is removed.'