So sánh hơn (comparative) và so sánh nhất (superlative) là cách nói X hơn Y hoặc X là nhất trong nhóm. Cấu trúc thay đổi theo độ dài tính từ: -er/-est cho tính từ ngắn, more/most cho tính từ dài. Dùng đúng cấu trúc so sánh giúp mô tả dữ liệu trong IELTS Writing Task 1 và phân tích xu hướng trong Task 2 chính xác hơn.
Tóm tắt
Tiếng Anh có ba mức so sánh:
| Mức |
Tên gọi |
Ý nghĩa |
Ví dụ |
| Bình thường |
Positive |
như nhau |
big, beautiful |
| So sánh hơn |
Comparative |
A hơn B |
bigger, more beautiful |
| So sánh nhất |
Superlative |
nhất trong nhóm |
the biggest, the most beautiful |
Tại sao quan trọng
So sánh xuất hiện liên tục trong IELTS:
- Writing Task 1: Sales were higher than the previous year / The UK had the highest rate of...
- Writing Task 2: Cities are more polluted than rural areas / Education is one of the most important investments...
- Speaking: This city is much bigger than my hometown / I prefer reading more than watching TV
Cấu trúc Comparative
Tính từ/Trạng từ ngắn (1 âm tiết, hoặc 2 âm tiết kết thúc -y)
Adjective + -er + than
| Tính từ |
Comparative |
Quy tắc thêm đuôi |
| tall |
taller |
thêm -er |
| nice |
nicer |
bỏ -e, thêm -er |
| big |
bigger |
nhân đôi phụ âm cuối |
| happy |
happier |
-y → -ier |
| easy |
easier |
-y → -ier |
- This book is cheaper than that one.
- She runs faster than him.
- My new job is easier than the old one.
Tính từ/Trạng từ dài (2+ âm tiết, không kết thúc -y)
more + Adjective + than
- This solution is more efficient than the previous one.
- She speaks more fluently than I do.
- Online shopping is more convenient than going to the store.
Bất quy tắc
| Dạng gốc |
Comparative |
Superlative |
| good / well |
better |
the best |
| bad / badly |
worse |
the worst |
| far |
further / farther |
the furthest / farthest |
| little |
less |
the least |
| much / many |
more |
the most |
| old |
older / elder |
the oldest / eldest |
- She's better at maths than her brother.
- Things got worse before they got better.
- I have less time today than yesterday.
Cấu trúc Superlative
Tính từ ngắn
the + Adjective + -est
| Tính từ |
Superlative |
| tall |
the tallest |
| nice |
the nicest |
| big |
the biggest |
| happy |
the happiest |
- He is the tallest student in the class.
- This is the cheapest option available.
Tính từ dài
the most + Adjective
- This is the most interesting book I've ever read.
- She's the most experienced candidate for the job.
- Tokyo is one of the most populated cities in the world.
Superlative + ever: Dùng Present Perfect sau superlative:
- It's the best film I've ever seen.
- That was the most difficult exam she'd ever taken.
Các cấu trúc so sánh quan trọng
1. As...as (so sánh bằng)
as + Adjective/Adverb + as
- She's as talented as her sister.
- The exam was not as difficult as I expected.
- He doesn't earn as much as she does.
Phủ định: not as...as = less...than
- This hotel is not as expensive as that one. = This hotel is less expensive than that one.
2. Much / Far / A lot / Even / Slightly (nhấn mạnh mức độ so sánh)
much / far / a lot / even / slightly + comparative
- The new model is much faster than the old one.
- She's far more qualified than the other applicants.
- Prices are slightly higher than last year.
- The second exam was even harder than the first.
Không dùng "very" với comparative:
- ❌ She's very taller than me.
- ✅ She's much taller / far taller than me.
3. The + comparative, the + comparative
Diễn tả mối quan hệ tỉ lệ thuận:
The + comparative..., the + comparative...
- The harder you work, the better your results.
- The more you practise, the more confident you become.
- The older he gets, the wiser he becomes.
4. Twice / Three times as...as (so sánh bội số)
twice / three times / half + as + Adjective + as
- The population of China is four times as large as that of the United States.
- This laptop costs twice as much as the one I bought last year.
- My commute is half as long as my colleague's.
5. Less / The least (so sánh kém)
less + Adjective + than
the least + Adjective
- This approach is less effective than the traditional method.
- Of all the options, this one is the least expensive.
So sánh trong mô tả dữ liệu (IELTS Task 1)
| Cần diễn đạt |
Cấu trúc |
Ví dụ |
| A cao hơn B |
A is higher/greater than B |
Sales in 2020 were higher than in 2019. |
| A thấp hơn B |
A is lower/smaller than B |
UK rates were lower than those in the US. |
| A cao nhất |
A has the highest... |
China has the highest population. |
| A thấp nhất |
A has the lowest... |
Iceland has the lowest crime rate. |
| Gần bằng nhau |
A is almost as high as B |
France's figures were almost as high as Germany's. |
| Gấp đôi |
A is twice as high as B |
The rate in 2020 was twice as high as in 2010. |
| Chênh lệch nhỏ |
slightly / marginally higher/lower |
Figures were slightly higher in urban areas. |
| Chênh lệch lớn |
significantly / considerably higher |
Costs were significantly higher in London. |
Lỗi thường gặp
Lỗi 1: Dùng "more" với tính từ ngắn
- ❌ She is more tall than her brother.
- ✅ She is taller than her brother.
- ❌ This is more cheap than that.
- ✅ This is cheaper than that.
Lỗi 2: Quên "than" sau comparative
- ❌ My city is bigger my hometown.
- ✅ My city is bigger than my hometown.
Lỗi 3: Quên "the" trước superlative
- ❌ She is most intelligent student in class.
- ✅ She is the most intelligent student in class.
Lỗi 4: Dùng "very" thay "much/far" trước comparative
- ❌ He is very smarter than me.
- ✅ He is much smarter / far smarter than me.
Lỗi 5: Nhầm "good-better-best" và "well-better-best"
- ❌ She sings more good than him.
- ✅ She sings better than him.
- ❌ This is the most good restaurant.
- ✅ This is the best restaurant.
Lỗi 6: Dùng comparative thay superlative khi so sánh 3+ thứ
- ❌ Of the three candidates, she is more qualified.
- ✅ Of the three candidates, she is the most qualified.
Ứng dụng trong IELTS
Writing Task 1 — so sánh dữ liệu:
- Sales in France were considerably higher than those in Germany throughout the period.
- The proportion of people aged 65+ was the highest in Japan, at twice as much as in the UK.
- Urban areas showed slightly higher unemployment rates compared to rural regions.
- The greater the investment in education, the lower the poverty rate tended to be.
Writing Task 2 — phân tích và lập luận:
- City life is often far more stressful than rural living, due to noise, traffic, and high costs.
- Renewable energy is becoming increasingly competitive with fossil fuels.
- Education is arguably one of the most powerful tools for reducing inequality.
- People in developed countries consume significantly more resources than those in developing nations.
Speaking — mô tả và so sánh:
- My hometown is much smaller than Hanoi, but I think it's far more peaceful.
- I find speaking more challenging than writing, because you can't take time to think.
- The more I practise English, the more confident I feel using it.
Bài tập luyện
Chia dạng đúng: comparative hoặc superlative
- Paris is one of ___ (beautiful) cities in Europe.
- He's ___ (tall) than his father.
- The exam was ___ (difficult) than I expected.
- Of all the subjects, Maths is ___ (challenging) for me.
- She works ___ (hard) than anyone else in the office.
Sửa lỗi
- She is more old than her colleague.
- This coffee is the more expensive in the menu.
- He runs very faster than me.
- Of the two options, the first is most practical.
- London is bigger as Paris.
Đáp án
Chia dạng:
1. the most beautiful | 2. taller | 3. more difficult | 4. the most challenging | 5. harder
Sửa lỗi:
1. She is older than her colleague. (old → older, không dùng "more")
2. This coffee is the most expensive on the menu. (the + most + long adj; "in the menu" → "on the menu")
3. He runs much faster than me. (dùng much/far, không dùng very)
4. Of the two options, the first is more practical. (hai đối tượng → comparative, không superlative)
5. London is bigger than Paris. (dùng "than", không "as")
Tóm tắt nhanh
Tính từ ngắn (1-2 âm tiết): -er / the -est
- Thêm -er/-est: tall → taller → the tallest
- Nhân đôi phụ âm: big → bigger → the biggest
- -y → -ier/-iest: happy → happier → the happiest
Tính từ dài (3+ âm tiết): more / the most
- more beautiful / the most beautiful
Bất quy tắc: good→better→best | bad→worse→worst | much/many→more→most | little→less→least
Cấu trúc quan trọng:
- so sánh bằng: as...as
- nhấn mạnh: much / far / considerably / significantly + comparative
- tỉ lệ: the + comparative, the + comparative
- bội số: twice / three times as...as
Không dùng "very" trước comparative — dùng "much/far/a lot/even" thay thế!
Lỗi phổ biến — "more better" và bỏ "than"
Tiếng Việt "hơn" có thể đi với mọi tính từ. Người học VN bê "more" + đã-comparative-rồi → double comparative.
❌ "She is more better than him." → ✅ "She is better than him."
❌ "Hanoi is more bigger than Da Nang." → ✅ "Hanoi is bigger than Da Nang."
❌ "This problem is more more difficult." → ✅ "This problem is more difficult."
Quy tắc: Adjective ngắn (1 syllable, hoặc 2 syllables ending in -y) → -er. Adjective dài → more + adj. KHÔNG đi cùng nhau.
Lỗi 2: Bỏ "than"
Tiếng Việt có thể so sánh bằng juxtaposition: "tôi cao bạn" (= cao hơn). English bắt buộc "than".
❌ "She is taller me." → ✅ "She is taller than me."
❌ "Hanoi is older Saigon." → ✅ "Hanoi is older than Saigon."
Mẹo: Mọi comparative cần có ít nhất một trong: "than X" (so với X) hoặc context rõ ràng (e.g., "Which is bigger?" — câu trả lời ellipsis chấp nhận).