Cool MateCertainly vs It does
When to use each in English, with meaning, register, and examples.
Certainly
Top 1,000 (very common)A2adverb
It does
Top 2,000 (common)
Most common: Certainly
| Certainly | It does | |
|---|---|---|
| Pronunciation | 🇬🇧 /["/ˈsɜːtnli/"]/🇺🇸 /["/ˈsɜːrtnli/"]/ | 🇬🇧 //ɪt dʌz//🇺🇸 //ɪt dʌz// |
| Meaning | Definitely; for sure. | It is true or correct. |
| Example | Without treatment, she will **almost certainly** die. | If you say it’s going to rain, then it 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 | it does matter, it does make sense, it does happen |
| 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. | 'It does' is often confused with 'It do' in incorrect contexts., Users may forget to use 'does' for third person singular., Often omitted in responses, leading to incomplete answers. |
| 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 to confirm or affirm something. Common in conversations, but can be less formal in casual settings. |
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Frequently asked questions: Certainly vs It does
What's the difference between Certainly and It does?
Certainly: Definitely; for sure. It does: It is true or correct.
Which is more common: Certainly and It does?
Certainly is the most common in everyday English.
Can you show an example of each?
Certainly: Without treatment, she will **almost certainly** die. It does: If you say it’s going to rain, then it does.
Can I use Certainly and It does interchangeably?
Not always. Certainly and It 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.