Assure vs You can't promise somethin' like that

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

Assure

Top 1,000 (very common)B2verb

You can't promise somethin' like that

InformalTop 2,000 (common)
Most formal: AssureMost common: Assure
 AssureYou can't promise somethin' like that
Pronunciation🇬🇧 /["/əˈʃʊə(r)//əˈʃɔː(r)/","/əˈʃʊəz//əˈʃɔːz/","/əˈʃʊəd//əˈʃɔːd/","/əˈʃʊərɪŋ//əˈʃɔːrɪŋ/"]/🇺🇸 /["/əˈʃʊr/","/əˈʃʊrz/","/əˈʃʊrd/","/əˈʃʊrɪŋ/"]/🇬🇧 //juː kɑːnt ˈprɒmɪs ˈsʌmθɪŋ laɪk ðæt//🇺🇸 //ju kɑnt ˈprɑmɪs ˈsʌmθɪŋ laɪk ðæt//
MeaningTo make someone feel sure about somethingYou cannot make a promise about something like that.
ExampleI assure you that everything will be fine.You can't promise somethin' like that; it's just too risky.
RegisterNeutralInformal
How commonTop 1,000 (very common)Top 2,000 (common)
CEFR levelB2-
Part of speechverb
Collocationscan, hasten to, of, let me assure youmake a promise, keep a promise, promise to help, promise someone, promise you won't
Antonymsdoubt, disprove, deny-
Common mistakesConfused with 'ensure' which means to make certain something happens., Using it without a direct object; 'I assure that...' is incorrect., Mixing up 'assure' with 'insure' which relates to insurance.'Promise' is often confused with 'guarantee', which have different meanings., Learners may forget to use 'that' after 'like' when trying to convey a specific example., 'Somethin'' is sometimes mistakenly written as 'something' in informal contexts.
Usage notesUse 'assure' when you want to promise someone that something is true or will happen. It’s often used in more formal situations. Avoid using it in casual conversations where simpler verbs like 'tell' or 'say' might fit better.Used in casual conversation, often implies doubt or impossibility about the promise made.

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Assure
You can't promise somethin' like that

Frequently asked questions: Assure vs You can't promise somethin' like that

What's the difference between Assure and You can't promise somethin' like that?

Assure: To make someone feel sure about something You can't promise somethin' like that: You cannot make a promise about something like that.

Which is more formal: Assure and You can't promise somethin' like that?

Assure is the most formal of these.

Which is more common: Assure and You can't promise somethin' like that?

Assure is the most common in everyday English.

Can you show an example of each?

Assure: I assure you that everything will be fine. You can't promise somethin' like that: You can't promise somethin' like that; it's just too risky.

Can I use Assure and You can't promise somethin' like that interchangeably?

Not always. Assure and You can't promise somethin' like that 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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