Process diagrams are usually a student's least favorite IELTS task 1 rubrics. Personally, I think they are much easier than some of the other tasks out there.
The first thing that we must remember is you need an overview.
The best kind of overview is to state the number of steps in the process, also include both the first and final steps. For example:
The diagram shows the production of milk, with x number of steps starting with cows grazing and ending with bottled milk delivery.
You can also mention what the result of this production is, tea? concrete? What do we have when the process is complete?
If there are a few different processes then compare them in your overview, and mention the number of stages. For example:
The process diagrams illustrate the production of five different teas, from harvest to packaging. There is also a diagram showing a similar six step process for coffee beans.
Here is a possible introduction for a hydroelectric process:
Power begins with the sun heating up the sea water and the process ends with hydroelectric power being pumped into hospitals and schools and factories for consumption.
You are allowed to use all the words that you see in the task, however, avoid using the language word for word that you had in the prompt.
So, in the actual test question itself, you don't want to copy pieces of that language, but you are most certainly allowed to use the words that appear here in the actual diagram.
Passive / active voice
Process diagrams test your ability to know when to use the passive and when to use the active voice.
Some verbs can't be used in the passive, to determine which voice to use, ask yourself, who is doing this action?
Do we know who is doing the action?
It can be a machine, a worker, nature or something else.
after which - can refer to the whole of the (action of the) preceding clause or sentence.
The milk is then filtered, after which it is sent to be bottled and packed.
Depending on the particular diagram, there are a lot of different verbs you could use and they are much simpler than you imagine.
Below is a list of useful verbs with their prepositions, some are in the passive and others in the active.
I think learning them with their prepositions is tremendously more effective than learning them as single words.
Processed by - The tea leaves are processed by a mixing machine.
Added to - The mixture is added to the raw product…
Passed onto - After drying, the tea leaves are passed onto the next stage.
Passes through - The clay passes through the pipe, to later form bricks.
Goes into - The water then goes into the main collection bowl…
Flows out of - The liquid flows out of the first container and into the bowl...
Placed into - After the first step, the tea leaves are placed under the dryer.
Enters a / the- The mixture enters a final stage before reaching the furnace.
Formed- The bricks are formed by molding machines.
Sent to / for- The final product is sent to the finishing stage
Enters- At this step the product enters the penultimate step before delivery.
Distribute - The product can now be distributed via the firm's logistics department.
Stored in the - After finishing, the bricks are stored in a dry chamber.
Transfer - The product is transferred to the nearest bakery.
Begins with - This process begins with the raw materials arriving at the loading bay.
For some processes, you could say that it is placed, which is passive voice or you could say it enters which is active voice. Both are grammatically correct.
It depends on the graphic you have to describe.
Object pronouns are especially helpful because they allow you to avoid repetition.
... following this step,
first, second, and finally
after this step is completed...
All the phrases below are suitable to use in a process diagram description, but please remember to adapt them to your specific rubric.
A multi step process ...
The process starts with … and ends at ....
We have a six step process, whereby water undergoes a purification process.
... which causes it to ...
The final product is sent to the finish stage ...
It consists of … steps starting with … and ending with / at.
It consists of seven steps, starting with cows grazing in the field and ending with milk products being stored in supermarkets and shop shelves.
You can download or listen to the audio version here:
You can also watch the full tutorial here:
Take a look at our sample academic task 1 essays here.