Definitely vs Sure they would

When to use each in English, with meaning, register, and examples.

Definitely

Top 1,000 (very common)A2adverb

Sure they would

Beyond 10,000 (less common)
Most common: Definitely
 DefinitelySure they would
Pronunciation🇬🇧 /["/ˈdefɪnətli/"]/🇺🇸 /["/ˈdefɪnətli/"]/🇬🇧 //ʃʊə ðeɪ wʊd//🇺🇸 //ʃʊr ðeɪ wəd//
MeaningFor sure, without a doubtYes, they probably would do that.
ExampleI definitely remember sending the letter.If you ask them to join, sure they would.
RegisterNeutralNeutral
How commonTop 1,000 (very common)Beyond 10,000 (less common)
CEFR levelA2-
Part of speechadverb
Collocationsdefinitely agree, definitely believe, definitely knowsure they would support, sure they would agree, sure they would help, sure they would understand, sure they would participate
Antonymsdoubtfully, uncertainly-
Common mistakesOften confused with 'defiantly' which means resisting authority., Sometimes spelled incorrectly as 'definately'.Using 'sure they will' instead of 'sure they would' when referring to past possibilities., Confusing with 'of course they would' which is more emphatic., Forgetting to use it only in conditional contexts.
Usage notesUse 'definitely' to emphasize certainty. It fits well in both spoken and written English. Avoid using it in overly formal contexts where alternatives like 'certainly' might be more suitable.Use this phrase to affirm someone's assumption about a group’s likely behavior. It's casual and often used in conversations.

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Definitely
Sure they would

Frequently asked questions: Definitely vs Sure they would

What's the difference between Definitely and Sure they would?

Definitely: For sure, without a doubt Sure they would: Yes, they probably would do that.

Which is more common: Definitely and Sure they would?

Definitely is the most common in everyday English.

Can you show an example of each?

Definitely: I definitely remember sending the letter. Sure they would: If you ask them to join, sure they would.

Can I use Definitely and Sure they would interchangeably?

Not always. Definitely and Sure they would 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.

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