Cool MateSure as he's born vs Undoubtedly
When to use each in English, with meaning, register, and examples.
Sure as he's born
InformalBeyond 10,000 (less common)
Undoubtedly
FormalTop 5,000 (fairly common)C1adverb
Most formal: UndoubtedlyMost common: Undoubtedly
| Sure as he's born | Undoubtedly | |
|---|---|---|
| Pronunciation | 🇬🇧 //ʃʊə əz hiːz bɔːn//🇺🇸 //ʃʊr əz hiz bɔrn// | 🇬🇧 //ʌnˈdaʊtɪdli//🇺🇸 //ʌnˈdaʊtədli// |
| Meaning | certain or sure | Definitely; without a doubt. |
| Example | I will be there tomorrow, sure as he's born. | She is undoubtedly the best candidate for the position. |
| Register | Informal | Formal |
| How common | Beyond 10,000 (less common) | Top 5,000 (fairly common) |
| CEFR level | - | C1 |
| Part of speech | adverb | |
| Collocations | sure as can be, sure as usual | undoubtedly true, undoubtedly clear, undoubtedly helpful |
| Antonyms | uncertain, unlikely, doubtful | doubtfully, questionably, uncertainly |
| Common mistakes | Using in formal writing contexts, Confusing with similar expressions like 'sure as sugar', Misplacing the phrase within sentences | Confused with 'undoubtably', which is incorrect., Omitting it when certainty is implied., Using it in informal contexts where 'definitely' is more suitable. |
| Usage notes | Used often in spoken language, this phrase conveys strong certainty about something. It's not typically used in formal writing or situations. | Used to emphasize certainty or strong belief; typically in formal writing or speeches, not common in casual conversation. |
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Frequently asked questions: Sure as he's born vs Undoubtedly
What's the difference between Sure as he's born and Undoubtedly?
Sure as he's born: certain or sure Undoubtedly: Definitely; without a doubt.
Which is more formal: Sure as he's born and Undoubtedly?
Undoubtedly is the most formal of these.
Which is more common: Sure as he's born and Undoubtedly?
Undoubtedly is the most common in everyday English.
Can you show an example of each?
Sure as he's born: I will be there tomorrow, sure as he's born. Undoubtedly: She is undoubtedly the best candidate for the position.
Can I use Sure as he's born and Undoubtedly interchangeably?
Not always. Sure as he's born and Undoubtedly 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.