The error examiners see most
Many languages have no articles at all, so there is nothing in your head to copy from. That is why smart writers with good ideas still drop a "the" in half their sentences. Here is the useful part. You do not need the whole grammar of articles. Almost every mistake in a real IELTS essay comes from only three situations.
The three questions to ask
01Am I talking about a group in general?
02Can the reader already tell which one I mean?
03Is it one of many, mentioned for the first time?
6 article fixes worth memorizing
General statements
✕The people today spend too much time on the phones.
✓People today spend too much time on their phones.
You mean people in general, not a group you already named. General plural means no article. This single fix cleans up more sentences than any other.
Only one of it in the world
✕Factories are damaging environment.
✓Factories are damaging the environment.
There is only one environment, so the reader already knows which one you mean. Same for the internet, the government, the economy, the weather, the past.
Society is the odd one
✕This is a serious issue in the society.
✓This is a serious issue in society.
"Society" works like a general idea, so it takes no article, even though "the government" and "the economy" do take one. It appears in thousands of essays, so it is worth learning as a fixed phrase.
A or An follows sound
✕She went to an university to study for a hour.
✓She went to a university to study for an hour.
Choose by the SOUND of the next word, not the letter. University starts with a "yu" sound, so it takes "a". Hour starts with a vowel sound because the h is silent, so it takes "an". Also: an MBA, an hour, a European country.
Second mention
✕A study found a problem. A problem is getting worse.
✓A study found a problem. The problem is getting worse.
First time you introduce it, use "a". After that the reader knows which one, so it becomes "the". This is the whole system in one sentence.
Superlatives always take the
✕Education is most important factor.
✓Education is the most important factor.
The best, the worst, the most, the least, the first, the same. If there can only be one of them, it takes "the". No exceptions to remember.
Fixed phrases to learn as whole units
✓in society, in modern society (no "the")
✓the environment, the internet, the government, the media
✓in the past, in the future, at the moment
✓go to school, go to university, go to work (no article when you mean the activity)
✓the United States, the UK, the Netherlands (but no "the" for France, Japan, Brazil)
What to do when you are not sure in the exam
Do not freeze. An article slip is a small error, and stopping for two minutes to solve it is a much bigger one, because you lose the words and the ideas you could have written instead. Make your best guess and keep moving. If you truly cannot decide, rewrite the sentence in the general plural, which needs no article at all. "The role of a teacher is important" can simply become "Teachers matter".
Read next
More grammar that moves your score: 6 mistakes that make your IELTS score drop fast and the 4 questions your examiner is secretly asking.
Find the ones you keep repeating
Article errors are a habit, not bad luck. Most students repeat the same two or three patterns in every essay, and once you see yours written out, they are surprisingly easy to break. Write your next essay in VoyaLang and look at the correction list. Each article fix is shown in the sentence you actually wrote, so you learn your own pattern instead of a general rule. Create a free account and check your next essay in about a minute.