IELTS Writing Task 1: So Sánh Số và Tỉ Lệ Trong Pie Chart

IELTS Writing Task 1: Comparing Numbers and Percentages

Mục tiêu của bài này

Trong IELTS Writing Task 1, em không nên mô tả từng con số như các thông tin riêng lẻ.

Ví dụ:

Hot coffee sales were 75 servings in winter.
Hot coffee sales were 30 servings in summer.

Hai câu trên đúng về dữ liệu, nhưng người đọc phải tự nhận ra sự khác biệt.

Một câu tốt hơn là:

Hot coffee sales were about 75 servings in winter, compared with 30 in summer.

Câu này vừa đưa số liệu, vừa cho người đọc thấy ngay mối quan hệ giữa hai con số.

Trong bài này, em sẽ tập trung vào một kỹ năng có thể dùng cho nhiều dạng biểu đồ:

GROUP → COMPARE → WRITE

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1. Đừng viết từng con số — hãy tìm mối quan hệ

Khi nhìn vào biểu đồ, đừng hỏi:

“Con số tiếp theo là bao nhiêu?”

Hãy hỏi:

“Những số liệu nào nên được đặt cạnh nhau để tạo thành một comparison có ý nghĩa?”

Ví dụ: Average daily sales

Thay vì viết 10 số liệu riêng biệt, có thể chia thành 3 nhóm:

Winter was higher

• hot coffee
• soup

Summer was higher

• iced coffee
• ice cream

Similar / unchanged

• salad

Đây là kỹ năng quan trọng:

Many numbers → a few useful relationships

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2. Structure 1: X ..., compared with Y ...

Function

Dùng để đặt hai con số cạnh nhau và cho người đọc thấy sự khác biệt ngay lập tức.

Form

X + verb + number, compared with + number + for Y.

Example

Hot coffee sales stood at about 75 servings in winter, compared with 30 in summer.

Another example

Approximately 600 under-11s attended ballet classes, compared with around 300 students aged 11–16.

IELTS job

compared with giúp em:

• tránh viết hai câu rời rạc;
• làm comparison rõ hơn;
• nhóm dữ liệu có liên quan trong cùng một câu.

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3. Structure 2: while

Function

Dùng để contrast hai nhóm hoặc hai xu hướng trong cùng một câu.

Form

X + clause, while + Y + clause.

Example

Iced coffee was considerably more popular in summer, while hot coffee was much more popular in winter.

Example with numbers

Around 600 under-11s attended ballet, while the figure for 11–16-year-olds was about 300.

Remember

while không chỉ là từ nối. Trong Task 1, nó có một job cụ thể:

show a contrast clearly

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4. Numbers vs percentages

Đây là phần quan trọng khi chuyển từ bar chart sang pie chart hoặc mixed charts.

Khi dữ liệu là số lượng

Dùng:

• the number of + plural noun
• the figure for + category

Examples

The number of under-11s attending ballet was approximately 600.

The figure for older students was around 300.

Common mistake

❌ the figure of older students
✅ the figure for older students

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Khi dữ liệu là phần trăm

Dùng:

• accounted for + %
• made up + %
• represented + %

Examples

Private studios accounted for 48% of all dance-class locations.

School halls made up 24% of the total.

Community halls and other venues represented 18%.

Common mistake

❌ Private studios accounted 48%.
✅ Private studios accounted for 48%.

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5. Compare percentages with percentages

Consider this data:

A weak description is:

Private studios were 48%. School halls were 24%. Community halls were 18%. College-based studios were 10%.

The data is correct, but it is mostly a list.

A stronger description is:

Private studios accounted for 48% of all locations, compared with 24% for school halls. Community halls and other venues made up 18%, while college-based studios represented the smallest share, at just 10%.

The stronger version does three things:

1. groups related categories;
2. shows ranking and contrast;
3. uses percentage language accurately.

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6. Do not compare different units directly

A mixed Task 1 may contain different units.

For example:

• pie chart → percentages
• bar chart → number of students

Do not write:

❌ Private studios accounted for 48%, compared with 600 ballet students.

The units are different and the comparison does not make sense.

Instead:

Compare within the pie chart

Private studios accounted for 48%, compared with 24% for school halls.

Compare within the bar chart

Around 600 under-11s attended ballet, compared with approximately 300 students aged 11–16.

Rule

% ↔ %
students ↔ students

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7. From individual bars to groups

Consider these dance-class figures:

Do not simply write:

Ballet had 600 younger students. Ballet had 300 older students. Tap had 450 younger students...

Instead, identify the relationships first.

Ballet

Much more popular among younger students.

Approximately 600 under-11s attended ballet, compared with around 300 students aged 11–16.

Modern

The opposite pattern.

Modern dance showed the opposite pattern, with just over 500 older students, compared with around 300 younger children.

Tap

The two age groups were relatively similar.

Tap attracted relatively similar numbers from the two age groups.

The goal is not to mention every number mechanically.

The goal is to show the reader:

What is higher? What is lower? What is similar? What is unusual?

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8. Writing the overview

The overview should show the main patterns, not become another body paragraph.

For the dance-class charts, useful overview ideas are:

• private studios = most common location;
• college-based studios = least common location;
• ballet = more popular among under-11s;
• modern = more popular among 11–16-year-olds.

Model overview

Overall, private studios were the most common location for dance classes, while college-based studios were the least common. In terms of class type, ballet was considerably more popular among children under 11, whereas modern dance was preferred by those aged 11–16.

Notice:

• no unnecessary detail;
• no list of every category;
• clear highest / lowest information;
• clear age-group contrast.

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9. Model body paragraph: percentages

Private studios accounted for 48% of all class locations, which was twice the figure for school halls, at 24%. Community halls and other venues represented 18% of the total, while college-based studios made up the smallest proportion, at just 10%.

What is the paragraph doing?

It does not simply report four percentages.

It shows:

largest → comparison → smaller groups → smallest

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10. Model body paragraph: numbers

Approximately 600 children under 11 attended ballet classes, compared with around 300 students aged 11–16. The opposite pattern can be seen for modern dance, with just over 500 older students participating compared with about 300 younger children. Tap attracted relatively similar numbers in the two groups.

What is the paragraph doing?

It groups the bars according to relationships:

• strong younger preference;
• strong older preference;
• similar participation.

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11. A simple Task 1 process

Before writing, follow these four steps.

Step 1 — Identify the unit

Is the chart showing:

• numbers?
• percentages?
• money?
• time?
• another unit?

Step 2 — Find the strongest patterns

Look for:

• highest;
• lowest;
• large differences;
• similarities;
• opposite patterns.

Step 3 — Group related data

Do not follow the chart mechanically from left to right.

Group figures that create a useful comparison.

Step 4 — Choose language for the job

For numbers:

the number of / the figure for

For percentages:

accounted for / made up / represented

For comparison:

while / compared with

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12. Final checklist

Before finishing a Task 1 paragraph, ask:

• Am I comparing, or only listing?
• Have I grouped related data?
• Am I using the correct language for the unit?
• Did I write the figure for, not the figure of?
• Did I write accounted for, not accounted?
• Does my overview show the main patterns without too many figures?

Remember

GROUP → COMPARE → WRITE

The grammar is useful because it helps the reader understand the relationship between the data.