Cool MateCertainly vs Of course you will
When to use each in English, with meaning, register, and examples.
Certainly
Top 1,000 (very common)A2adverb
Of course you will
Top 2,000 (common)
Most common: Certainly
| Certainly | Of course you will | |
|---|---|---|
| Pronunciation | 🇬🇧 /["/ˈsɜːtnli/"]/🇺🇸 /["/ˈsɜːrtnli/"]/ | 🇬🇧 //əv kɔːs ju wɪl//🇺🇸 //əv kɔrs ju wɪl// |
| Meaning | Definitely; for sure. | It's certain that you will do it. |
| Example | Without treatment, she will **almost certainly** die. | When you asked if you would pass the test, I said, 'Of course you will!' |
| Register | Neutral | Neutral |
| How common | Top 1,000 (very common) | Top 2,000 (common) |
| CEFR level | A2 | - |
| Part of speech | adverb | |
| Collocations | certainly agree, certainly possible, certainly not, certainly true, certainly yes | Of course you can, Of course not, Of course we will |
| Antonyms | uncertainly, doubtfully | - |
| Common mistakes | 'Certainly' is often incorrectly used in place of 'certain' in adjectives., Learners might confuse 'certainly' with 'definitely' without noticing the subtle nuance., Some learners use 'certainly' in inappropriate contexts, such as casual greetings. | Using 'of course you will' in a sarcastic tone when it doesn't apply., Confusing with 'of course not', which expresses a negative sentiment., Relying on it in formal presentations. |
| Usage notes | Use 'certainly' when you want to emphasize affirmation or agreement. It is more formal than 'sure' and works well in professional settings, but might feel too strong in casual conversations. | Commonly used in conversations to express certainty or assurance. Suitable in both spoken and written contexts. Avoid in overly formal writing. |
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Frequently asked questions: Certainly vs Of course you will
What's the difference between Certainly and Of course you will?
Certainly: Definitely; for sure. Of course you will: It's certain that you will do it.
Which is more common: Certainly and Of course you will?
Certainly is the most common in everyday English.
Can you show an example of each?
Certainly: Without treatment, she will **almost certainly** die. Of course you will: When you asked if you would pass the test, I said, 'Of course you will!'
Can I use Certainly and Of course you will interchangeably?
Not always. Certainly and Of course you will 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.