Here's the thing most students don't realize: grammar errors in Task 1 aren't just minor deductions. They crater your entire Grammatical Range & Accuracy score—which is 25% of your writing mark. You could nail task response and get excellent coherence, but careless grammar drags you from Band 7 straight down to Band 5.
The good news? Most grammar mistakes aren't complicated. They're the same errors showing up in hundreds of student essays. You're about to learn how to spot them using the same techniques an IELTS writing checker would use.
Task 1 is technical writing. You're describing charts, diagrams, processes, or maps. Examiners expect precision with subject-verb agreement, tense consistency, and complex sentences. One misplaced verb or confused subject tanks your credibility instantly.
The IELTS band descriptors spell this out. Band 7 requires "a variety of complex structures" with only "occasional errors". Band 6 allows more mistakes, but they're noticeable. Band 5? That's where uncontrolled errors live.
Here's what happens in real time: you've got 20 minutes to describe a graph or process. Speed kills grammar. That's exactly when you need a mental checklist—something to catch errors before they matter.
Let me be direct. These five mistakes show up constantly in IELTS essay writing. Fix just these common grammar mistakes in Task 1, and you'll jump at least half a band.
This is the number one killer. You write a subject, then pick a verb that doesn't match it.
Weak: "The data shows that the majority of consumers is choosing online shopping."
The subject here is "majority" (singular), so you'd expect "is". But "choosing" sits in plural territory. Here's the fix:
Good: "The data shows that the majority of consumers are choosing online shopping."
Wait—didn't we just say "majority" is singular? Right. But "majority of consumers" (the actual subject here) is plural. The trick: ignore the collective noun and find the real subject underneath (consumers, plural).
You start in past tense, then slip into present. Examiners notice this immediately when they check grammar in IELTS writing.
Weak: "In 2019, the unemployment rate declined sharply. By 2021, it rises again, reaching 7.2%."
You bounced from past (declined) to present (rises). Disorienting. Pick one and stick with it:
Good: "In 2019, the unemployment rate declined sharply. By 2021, it had risen again, reaching 7.2%."
Prepositions trip up most non-native speakers. You see "increase to", "decrease from", "change at" when the real patterns are "increase by", "decrease to", and "change over".
Weak: "The sales increased from 40% to 65%, representing a rise of 25%."
The prepositions are technically possible, but the phrasing feels clunky. Tighten it:
Good: "Sales rose from 40% to 65%, an increase of 25 percentage points."
This haunts 90% of students whose native language doesn't use articles. You write "The chart shows that majority" or "A graph illustrates change" when you mean "the chart shows that the majority" or "the graph illustrates a change". These grammar errors in IELTS writing reduce your Grammatical Range & Accuracy score substantially.
Weak: "Table provides information about consumption of energy in countries."
Missing articles wreck fluency. Here's the corrected version:
Good: "The table provides information about the consumption of energy in different countries."
You start a sentence with a description, then the actual subject doesn't match what's being described.
Weak: "Examining the bar chart closely, the results were surprising."
Who's examining? The results? No. A person is. Fix it by naming the actual subject:
Good: "When examining the bar chart closely, we can see that the results are surprising."
You've finished Task 1 with 3 minutes left. What do you check first?
Don't read it normally. Your brain skips mistakes because it knows what you meant. Instead, use this targeted checklist to evaluate grammar errors and band score impact:
That's under 6 minutes total. You'll catch most errors that hurt your band score.
Tip: Read your essay out loud in the last 2 minutes. Your ear catches what your eyes miss. Weird phrasing, awkward rhythm, and repeated words jump out when you hear them.
Different chart types trigger different errors. Here's how to protect yourself in each one.
You're comparing multiple lines across time periods. Tense shifts happen because you're jumping between years.
Weak: "The blue line rises steadily from 2010 to 2015. It represents sales performance. Then the line falls to 20% by 2020."
The tenses are inconsistent and the rhythm is choppy. Combine them into one smooth sentence:
Good: "The blue line represents sales performance and rose steadily from 2010 to 2015 before falling to 20% by 2020."
Subject-verb agreement breaks down when you're comparing groups.
Weak: "The number of students in engineering and science have increased dramatically."
"Number" is singular. It takes "has", not "have":
Good: "The number of students in engineering and science has increased dramatically."
You're explaining steps in order. Passive voice works well here, but inconsistency breaks the flow.
Weak: "First, water is being heated. Then it is pumped to the tank. The tank stores it."
You switched from passive to active voice. Keep it consistent:
Good: "First, water is heated. It is then pumped to the tank, where it is stored."
The IELTS writing checker used by examiners focuses on two criteria: accuracy and range. A single grammar error isn't catastrophic, but patterns of errors drag your Grammatical Range & Accuracy score down visibly.
A grammar error breaks the rules: subject-verb disagreement, wrong tense, missing articles in formal writing. Examiners mark these directly against the Grammatical Range & Accuracy descriptor.
A style issue is clunky but technically correct. Example: "In 2019, the consumption of electricity by households was 45 units." It's wordy and passive, but grammatically sound. You might lose points on Coherence or Lexical Resource, not Grammar.
Fix actual errors first. Then polish style. That's how you move the needle on your band score.
Every student has weak spots. Yours might be articles. Your classmate's might be prepositions.
Next time you get feedback on a practice essay, write down every grammar comment. Look for patterns. Those three to five errors are your "personal corrections list". Write them on a sticky note and tape it to your desk. In your next practice essay, scan for only those specific mistakes.
This is faster than trying to catch every possible error. You're training your brain to notice your specific problems, not generic rules.
Tip: Keep a running document of sentences you wrote and then corrected. After 10-15 corrections, patterns emerge. You'll start catching those errors before they hit the page.
Let's look at a full paragraph from an actual Task 1 prompt. The question asks you to describe a pie chart showing household expenditure.
Band 5 version (grammar errors everywhere):
Weak: "The pie chart show the expenditures of a household on different category. Housing represent the largest proportion with 45%. Food takes 25%, and the rest of categories is distributed among transportation, entertainment and utilities. The chart demonstrates that majority of the money go to housing and food, which account nearly 70% of budget."
Count the errors: "show" (needs "shows"), "category" (needs "categories"), "represent" (needs "represents"), "is" (needs "are"), "go" (needs "goes"), "account" (needs "accounts"). Six errors in four sentences. That's a Band 5 ceiling.
Band 7 version:
Good: "The pie chart illustrates household expenditure across different categories. Housing represents the largest proportion at 45%, followed by food at 25%. The remaining budget is distributed among transportation, entertainment, and utilities. Notably, these two categories account for nearly 70% of total household spending, indicating that essential expenses dominate household budgets."
Every verb agrees with its subject. Tenses stay consistent. Articles are correct. Prepositions are precise. The writing flows naturally. That's a Band 7 response on grammar alone—even before considering other criteria.
Online grammar checkers like Grammarly catch basic errors: missing punctuation, obvious subject-verb disagreement, and repeated words. They're useful as a first pass before you manually check grammar in IELTS writing.
But they miss context-dependent mistakes and don't understand IELTS conventions. They'll sometimes flag correct British English as "wrong" or suggest changes that sound unnatural in academic writing. Use them to spot obvious issues, but don't trust them completely.
Your own careful reading—using the 5-minute checklist above—is always more reliable than an automated IELTS essay checker.
Use our free IELTS writing checker to analyze grammar errors, vocabulary, and your band score estimate. Get targeted corrections before exam day.
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