Cool MateImpossible vs It can't be
When to use each in English, with meaning, register, and examples.
Impossible
Top 1,000 (very common)A2
It can't be
Top 2,000 (common)
Most common: Impossible
| Impossible | It can't be | |
|---|---|---|
| Pronunciation | 🇬🇧 /["/ɪmˈpɒsəbl/"]/🇺🇸 /["/ɪmˈpɑːsəbl/"]/ | 🇬🇧 //ɪt kɑːnt biː//🇺🇸 //ɪt kænt bi// |
| Meaning | Not able to happen or be done. | It is not possible. |
| Example | Climbing that mountain seems impossible without proper training. | When he said he could lift that car, I thought, 'It can't be!' |
| Register | Neutral | Neutral |
| How common | Top 1,000 (very common) | Top 2,000 (common) |
| CEFR level | A2 | - |
| Collocations | appear, be, look, absolutely, completely, downright, for, be, become, find somebody, really, absolutely, completely | it can't be true, it can't be real, it can't be happening, it can't be serious |
| Antonyms | possible, feasible, achievable | - |
| Common mistakes | 'Impossible' is sometimes confused with 'unbelievable' but they are not the same., Learners might use 'impossible' to describe very challenging tasks instead of things that cannot be done at all., 'Impossible' is often incorrectly combined with less strong modifiers, like 'very impossible'. | Omitting 'it' and saying just 'can't be'., Using 'can't' in very formal speech., Confusing with 'it shouldn’t be' which implies advice rather than disbelief. |
| Usage notes | Use 'impossible' to describe something that cannot be achieved. It’s suitable for both spoken and written English but may be too strong in polite contexts. | Used to express disbelief or rejection of a statement. Appropriate in both spoken and written contexts. Avoid in overly formal settings. |
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Frequently asked questions: Impossible vs It can't be
What's the difference between Impossible and It can't be?
Impossible: Not able to happen or be done. It can't be: It is not possible.
Which is more common: Impossible and It can't be?
Impossible is the most common in everyday English.
Can you show an example of each?
Impossible: Climbing that mountain seems impossible without proper training. It can't be: When he said he could lift that car, I thought, 'It can't be!'
Can I use Impossible and It can't be interchangeably?
Not always. Impossible and It can't be are related and overlap in some contexts, but they differ in register, how common they are, and usage, so swapping one for another can change the meaning or tone. Check the differences above before substituting.