Cool MateCertainly vs Of course he does
When to use each in English, with meaning, register, and examples.
Certainly
Top 1,000 (very common)A2adverb
Of course he does
Top 2,000 (common)
Most common: Certainly
| Certainly | Of course he does | |
|---|---|---|
| Pronunciation | 🇬🇧 /["/ˈsɜːtnli/"]/🇺🇸 /["/ˈsɜːrtnli/"]/ | 🇬🇧 //əv kɔːs hi dʌz//🇺🇸 //əv kɔrs hi dʌz// |
| Meaning | Definitely; for sure. | This means you expect someone to agree or understand something obvious. |
| Example | Without treatment, she will **almost certainly** die. | He loves fishing, and when I asked if he would go this weekend, I said, 'Of course he does.' |
| 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 he does!, Of course she knows, Of course they agree, Of course you can, Of course it is |
| 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. | 'Of course he does' is sometimes used when 'Of course he doesn't' is correct, confusing agreement with disagreement., Learners may forget to use appropriate emphasis when speaking, making the affirmation sound weak., Some learners might use it in overly formal contexts where a direct answer is more suitable. |
| 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. | Used in conversations to affirm something obvious or expected. It's informal and may be perceived as slightly dismissive if overused. |
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Frequently asked questions: Certainly vs Of course he does
What's the difference between Certainly and Of course he does?
Certainly: Definitely; for sure. Of course he does: This means you expect someone to agree or understand something obvious.
Which is more common: Certainly and Of course he does?
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 he does: He loves fishing, and when I asked if he would go this weekend, I said, 'Of course he does.'
Can I use Certainly and Of course he does interchangeably?
Not always. Certainly and Of course he does 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.