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IELTS Writing 6 min read

IELTS Task 1 Vocabulary: Describing Data Precisely

Task 1 vocabulary is not about rare words. It is about precision: the right trend verb, an accurate degree adverb, and varying the grammar so five sentences do not share one pattern.

Lexical Resource is a quarter of your Task 1 score, and it is where candidates most often try the wrong fix. Reaching for unusual synonyms produces sentences that are technically varied and factually wrong — the figure catapulted to 40% is not better than rose sharply.

What the criterion actually rewards is precision and range: the right word for the movement, an accurate description of its size, and enough grammatical variety that five sentences do not all share one shape.

Trend verbs, sorted by what they mean

The mistake is treating these as interchangeable. They are not — each carries information about speed and size.

Upward

Word Implies
rise, increase, grow Neutral, any size
climb Steady, sustained
surge, rocket, soar Rapid and large
edge up, creep up Small and slow
recover, rebound Rising after a fall
peak (at) Reaching the highest point

Downward

Word Implies
fall, decrease, decline Neutral, any size
drop, dip Often short or sudden
plummet, plunge, collapse Rapid and large
slide, slip Gradual, often unwelcome
bottom out Reaching the lowest point
more than halve Precise, large

No change

level off, plateau, stabilise, remain constant, hold steady, show no significant change

Irregular

fluctuate, oscillate, vary, show no clear trend

Using plummet for a five-point fall is an error of degree, and examiners notice. Match the word to what the chart shows.

Degree adverbs

Pair a neutral verb with an accurate adverb and you get precision without risk:

Large: sharply, steeply, dramatically, substantially, considerably, markedly Moderate: moderately, noticeably, appreciably Small: slightly, marginally, fractionally Speed: rapidly, abruptly, suddenly / gradually, steadily, slowly

The figure rose steadily from 20% to 34%. (sustained, moderate) The figure rose sharply from 20% to 61%. (large, fast) The figure rose marginally from 20% to 22%. (small)

Three different facts, one verb. This is what range means in practice.

Approximation

Charts often do not give exact values. Saying 47% when the bar sits between gridlines is less accurate than approximating, and accuracy is what is scored.

approximately, around, about, roughly, just over, just under, slightly more than, marginally below, close to, in the region of, well above, nearly

The figure stood at just under 50% in 1990. Sales reached approximately 4.2 million units. Attendance was well above the average for the period.

Avoid almost exactly and precisely unless the chart genuinely labels the value.

Comparison language

Task 1 is comparison. These carry the work:

Multiples: twice as many as, three times higher than, more than double, half as many as, a third of Difference: by a margin of, compared with, in contrast to, whereas, while Superlatives: the highest, the lowest, the second largest, the least common Similarity: a similar pattern, comparable figures, followed the same trend, mirrored

Rental costs were more than double those of the previous decade. Germany recorded the highest figure, whereas Portugal recorded the lowest. Italy followed a similar trend, though at a consistently lower level.

Vary the grammar, not just the words

This is the highest-value habit in Task 1, and it does not require any new vocabulary. The same fact, five ways:

Pattern Example
Verb Sales rose sharply between 2001 and 2005.
Noun phrase There was a sharp rise in sales between 2001 and 2005.
Period as subject The years 2001 to 2005 saw a sharp rise in sales.
Participle clause Having risen sharply until 2005, sales then levelled off.
Adjective + noun 2005 marked the sharpest increase of the period.

A detail paragraph that cycles through three of these reads far better than one that repeats a single pattern, and it demonstrates the grammatical range the descriptors ask for.

Prepositions — the most common accuracy errors

These are small and they are marked.

Pattern Example
rise/fall from X to Y rose from 20% to 45%
rise/fall by X fell by 12 percentage points
rise/fall of X (with a noun) a decline of 8%
stand/remain at X stood at 60%
peak at X peaked at 74%
a rise in something a rise in unemployment
compared with / to compared with the previous year
between X and Y between 1990 and 2000
over a period over a ten-year period

Percent versus percentage point. If a figure moves from 20% to 30%, it rose by 10 percentage points, not 10 percent — 10 percent of 20 is 2. Using this correctly is a small, visible mark of precision.

Tense

Match the time frame the chart gives.

  • Past data: past simple. Production fell between 1980 and 1995.
  • No dates, or a process: present simple. The chart shows… The mixture is then heated.
  • Projected figures: future forms. Demand is expected to reach 5 million by 2030.
  • Mixed chart: switch tense as the time frame switches, and signal it clearly.

Process diagrams

Different vocabulary entirely — sequence, not trend.

Sequencers: first, initially, at the first stage, subsequently, following this, once this has been completed, finally Passive voice: is collected, are transferred, is then heated, has been filtered Purpose: in order to, so that, with the aim of

Once the pulp has been filtered, it is transferred to a drying chamber, where the remaining moisture is removed before packaging.

Process answers rarely contain figures, so the overview states how many stages there are and where the process begins and ends.

Maps

Position: to the north of, on the eastern edge, adjacent to, opposite, in the centre, surrounding Change: was demolished, was replaced by, was converted into, was extended, has been relocated to, made way for

The woodland to the south of the river was cleared and replaced by a residential development.

What not to do

  • Do not use a thesaurus you cannot verify. The figure escalated is wrong; escalate is for conflicts and costs, not chart lines.
  • Do not overstate. Plummeted for a small dip is a factual error.
  • Do not use idioms. Went through the roof is the wrong register for academic description.
  • Do not memorise sentence templates. Examiners recognise them, and they usually do not fit the specific chart.

Now put it into practice

Try it on your own work

Frequently asked questions

Do I need advanced vocabulary for IELTS Task 1?

No. You need accurate vocabulary. Lexical Resource rewards using the right word in the right collocation, and a precise common word beats a misused rare one every time.

How do I avoid repeating 'increase' and 'decrease'?

Vary the grammar rather than hunting for synonyms. The same idea can be a verb, a noun, or a participle clause, which gives you three different sentences without needing three different words.

Should I use exact figures or approximations?

Both. Use exact figures where the chart gives them clearly and approximations where it does not. Writing 'approximately 47%' when the chart shows a value between gridlines is more accurate than inventing a precise number.

What tense should I use in Task 1?

Match the time frame the chart gives. Past data takes the past simple; a chart with no dates or a process diagram takes the present simple; projected future figures take will or is expected to.

Written and reviewed by the Intellecta team

Checked against the published assessment criteria. How we write and review guides.

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