IELTS Academic Writing Task 1: How to Describe a Line Graph (Band 7 Trend Language)

The line graph is the most frequent visual in Academic Writing Task 1, and it is also the one where candidates lose the most easy marks. The task is always the same: you are given a graph showing how one or more figures change over a period of time, and you have 20 minutes to write at least 150 words describing it. What separates a Band 5 answer from a Band 7 is not fancy vocabulary — it is accurate trend language, the right tense, and a clear structure. This guide gives you all three.

Understand what the task rewards

Task 1 is marked on four equally weighted criteria: Task Achievement, Coherence and Cohesion, Lexical Resource, and Grammatical Range and Accuracy. For a line graph, Task Achievement means you have selected and reported the main trends, made comparisons, and included a clear overview. You do not need to mention every single data point — you need to spot the biggest movements and the highest and lowest values, then support them with a few well-chosen figures.

The four-paragraph structure

Almost every strong line-graph answer uses the same reliable shape:

1. Introduction (1 sentence): paraphrase the question. Change the words but keep the meaning.
2. Overview (2 sentences): state the biggest general trends with no specific numbers.
3. Body paragraph 1: describe one group of lines in detail, with data.
4. Body paragraph 2: describe the remaining lines in detail, with data.

The overview is the single most important paragraph — examiners look for it first, and a report without one is capped at Band 5 for Task Achievement. If you are unsure how to write it, read our dedicated guide to the Task 1 overview paragraph.

Get the tense right

The tense is decided by the dates on the horizontal axis, not by guesswork:

• Past dates (e.g. 1990–2015): use the past simple — "sales rose sharply."
• Future dates or "projected" data: use will / is expected to — "the figure is projected to double."
• No dates, or a general trend: use the present simple.

Mixing tenses at random is one of the fastest ways to lose Grammatical Accuracy marks, so check the axis before you start writing.

Trend vocabulary that actually scores

Lexical Resource on a line graph is really about describing movement precisely. Build your range around three ideas: direction, degree, and speed.

Verbs and nouns for direction

• Up: rise, increase, climb, grow, surge, soar (verbs); a rise, an increase, growth, a surge (nouns)
• Down: fall, decline, decrease, drop, plunge, dip (verbs); a fall, a decline, a drop, a slump (nouns)
• No change / flat: remain stable, level off, stay constant, plateau
• Change of direction: peak (reach a high point), bottom out, fluctuate (rise and fall irregularly)

Adjectives and adverbs for degree and speed

• Big + fast: a sharp rise / rose sharply; a dramatic increase / increased dramatically; a steep climb
• Small + slow: a slight fall / fell slightly; a gradual decline / declined gradually; a marginal drop
• Steady: a steady increase / rose steadily

Notice the grammar pattern: use an adjective before the noun ("a sharp rise") or an adverb after the verb ("rose sharply"). Varying between the two structures shows range and keeps your writing from sounding repetitive.

Model paragraph

Imagine a graph showing car sales in a country from 2000 to 2020. A Band 7 body paragraph might read:

"Sales of petrol cars began at around 500,000 units in 2000 and rose steadily to a peak of roughly 900,000 in 2010. After this, the figure fell sharply, plunging to just 300,000 by 2020. Electric car sales, by contrast, remained negligible until 2010 before climbing dramatically to overtake petrol vehicles in the final two years of the period."

Every sentence names a trend, supports it with an approximate figure, and uses a different piece of movement vocabulary. That combination is exactly what the descriptors reward.

Common mistakes to avoid

1. Listing every number. A graph is not a table — describe the shape of the lines, not each data point.
2. No overview. Without a clear summary of the main trends, Task Achievement is capped at Band 5.
3. Repeating "increase" and "decrease". Rotate your verbs and nouns; repetition drags down Lexical Resource.
4. Adding opinions. Task 1 is a factual report — never explain why a trend happened or say whether it is good.
5. Ignoring the word count. You must write at least 150 words; under-length answers are penalised.

How to practise

Pick one line graph, set a 20-minute timer, and write a full four-paragraph answer using at least five different pieces of trend vocabulary. Then check your work: paste it into our free AI IELTS essay checker for a criterion-by-criterion estimate, and use the band score calculator to see how a Task 1 score combines with Task 2 into your overall Writing band. Draft more timed reports from the IELTS Writing questions bank until the structure and trend language become automatic. Accurate movement vocabulary, the correct tense, and a clear overview are what carry a line-graph answer from Band 6 to Band 7.