Cool MateIndeed vs They certainly do
When to use each in English, with meaning, register, and examples.
Indeed
Top 1,000 (very common)B1adverb
They certainly do
Top 5,000 (fairly common)
Most common: Indeed
| Indeed | They certainly do | |
|---|---|---|
| Pronunciation | 🇬🇧 /["/ɪnˈdiːd/"]/🇺🇸 /["/ɪnˈdiːd/"]/ | 🇬🇧 //ðeɪ ˈsɜːtənli duː//🇺🇸 //ðeɪ ˈsɜrtənli du// |
| Meaning | Yes, really; for sure. | They really do something. |
| Example | Indeed, the project is going much better than we expected. | If you think they are friendly, they certainly do seem that way. |
| Register | Neutral | Neutral |
| How common | Top 1,000 (very common) | Top 5,000 (fairly common) |
| CEFR level | B1 | - |
| Part of speech | adverb | |
| Collocations | indeed true, indeed a fact, as you said, indeed | do say, do believe, do enjoy |
| Antonyms | disregarding, neglecting | - |
| Common mistakes | Using 'indeed' in extremely casual texts, where 'yes' would be more appropriate., Confusing 'indeed' with 'instead' — they have different meanings., Placing 'indeed' too far from what it modifies, making it unclear. | Confused with 'they certainly don't' which has an opposite meaning., Using it in overly formal contexts where a simple 'yes' is more appropriate. |
| Usage notes | Used to confirm something previously mentioned. Normal in both spoken and written English, but less common in very casual conversations. | Use this phrase to affirm or emphasize something that has been said. It's more emphatic than just saying 'yes'. Suitable for conversations but not very formal writing. |
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Frequently asked questions: Indeed vs They certainly do
What's the difference between Indeed and They certainly do?
Indeed: Yes, really; for sure. They certainly do: They really do something.
Which is more common: Indeed and They certainly do?
Indeed is the most common in everyday English.
Can you show an example of each?
Indeed: Indeed, the project is going much better than we expected. They certainly do: If you think they are friendly, they certainly do seem that way.
Can I use Indeed and They certainly do interchangeably?
Not always. Indeed and They certainly do 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.