Cool MateUncertainty vs What i don't know
When to use each in English, with meaning, register, and examples.
Uncertainty
Top 1,000 (very common)B2noun
What i don't know
Top 3,000 (common)
Most common: Uncertainty
| Uncertainty | What i don't know | |
|---|---|---|
| Pronunciation | 🇬🇧 /["/ʌnˈsɜːtnti/"]/🇺🇸 /["/ʌnˈsɜːrtnti/"]/ | 🇬🇧 //wɒt aɪ doʊnt noʊ//🇺🇸 //wɑt aɪ doʊnt noʊ// |
| Meaning | Not being sure about something. | Things I am not aware of. |
| Example | The uncertainty about the future made it difficult for her to make long-term plans. | I can't help you with that; it's just what I don't know. |
| Register | Neutral | Neutral |
| How common | Top 1,000 (very common) | Top 3,000 (common) |
| CEFR level | B2 | - |
| Part of speech | noun | |
| Collocations | considerable, great, high, amount, degree, element, cause, create, generate, surround something, exist, remain, uncertainty about, uncertainty as to, uncertainty in, an area of uncertainty, an atmosphere of uncertainty, a climate of uncertainty, considerable, great, high, amount, degree, element, cause, create, generate, surround something, exist, remain, uncertainty about, uncertainty as to, uncertainty in, an area of uncertainty, an atmosphere of uncertainty, a climate of uncertainty | what I don't understand, what I don't remember, what I don't believe |
| Antonyms | certainty, assurance, confidence | what I do know, knowledge, understanding |
| Common mistakes | Confusing 'uncertainty' with 'insecurity' which has different meanings., Using 'uncertainty' in situations that require more concrete terms., Not differentiating between 'uncertainty' as a state and the causes of that uncertainty. | Confused with 'what I do know'., Misused in affirmative sentences., Used incorrectly as a question. |
| Usage notes | Use 'uncertainty' in formal discussions, such as scientific or academic contexts. Avoid it in casual conversations where simpler words like 'doubt' may be more appropriate. | Use this phrase when expressing uncertainty or lack of knowledge. It's appropriate in both casual and formal conversations. |
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Frequently asked questions: Uncertainty vs What i don't know
What's the difference between Uncertainty and What i don't know?
Uncertainty: Not being sure about something. What i don't know: Things I am not aware of.
Which is more common: Uncertainty and What i don't know?
Uncertainty is the most common in everyday English.
Can you show an example of each?
Uncertainty: The uncertainty about the future made it difficult for her to make long-term plans. What i don't know: I can't help you with that; it's just what I don't know.
Can I use Uncertainty and What i don't know interchangeably?
Not always. Uncertainty and What i don't know 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.