Cool MateCertain vs Sure
When to use each in English, with meaning, register, and examples.
Certain
Top 1,000 (very common)A2adjective
Sure
Top 1,000 (very common)A1adjective
| Certain | Sure | |
|---|---|---|
| Pronunciation | 🇬🇧 /["/ˈsɜːtn/"]/🇺🇸 /["/ˈsɜːrtn/"]/ | 🇬🇧 /["/ʃʊə(r)//ʃɔː(r)/"]/🇺🇸 /["/ʃʊr/"]/ |
| Meaning | sure, without any doubt | certain or confident about something |
| Example | I am certain that I locked the door before leaving. | I am sure that we will win the game. |
| Register | Neutral | Neutral |
| How common | Top 1,000 (very common) | Top 1,000 (very common) |
| CEFR level | A2 | A1 |
| Part of speech | adjective | adjective |
| Collocations | be, feel, look, very, absolutely, quite, about, of, can’t say for certain, not know for certain, be, feel, look, very, absolutely, quite, about, of, can’t say for certain, not know for certain | be, feel, seem, absolutely, completely, quite, about, of, be, feel, seem, absolutely, completely, quite, about, of |
| Antonyms | uncertain, doubtful, indefinite | uncertain, doubtful, unsure |
| Common mistakes | Confused with 'sure' in different contexts., Using 'certain' without clarifying what is certain about., Incorrectly using 'certain' to describe someone as a person (should be used for objects or ideas). | Used too casually in formal situations., Confused with 'surely' which implies a stronger confirmation., Mispronounced as 'sher' instead of 'shur'. |
| Usage notes | Use 'certain' when you want to express confidence in something. It's appropriate in both spoken and written English, but avoid it in very formal contexts where 'specific' or 'determined' may be better. | Used to express agreement or assurance. It's typically appropriate in most casual and formal contexts, but can feel dismissive if overused in a conversation. |
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Frequently asked questions: Certain vs Sure
What's the difference between Certain and Sure?
Certain: sure, without any doubt Sure: certain or confident about something
Which is more advanced: Certain and Sure?
Certain is the highest level, at A2, on the CEFR scale.
Are Certain and Sure the same CEFR level?
Certain: A2, Sure: A1 on the CEFR scale.
What part of speech are Certain and Sure?
Certain: adjective, Sure: adjective.
Can you show an example of each?
Certain: I am certain that I locked the door before leaving. Sure: I am sure that we will win the game.
Can I use Certain and Sure interchangeably?
Not always. Certain and Sure 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.