A promise is a promise vs Guarantee

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

A promise is a promise

Common idiom

Guarantee

Top 2,000 (common)B2verb
Most common: Guarantee
 A promise is a promiseGuarantee
Pronunciation🇬🇧 //ə ˈprɒmɪs ɪz ə ˈprɒmɪs//🇺🇸 //ə ˈprɑːmɪs ɪz ə ˈprɑːmɪs//🇬🇧 /["/ˌɡærənˈtiː/","/ˌɡærənˈtiːz/","/ˌɡærənˈtiːd/","/ˌɡærənˈtiːɪŋ/"]/🇺🇸 /["/ˌɡærənˈtiː/","/ˌɡærənˈtiːz/","/ˌɡærənˈtiːd/","/ˌɡærənˈtiːɪŋ/"]/
MeaningA promise means you must do what you said.A promise that something will happen or be done.
ExampleWhen he said he would help me, I knew a promise is a promise.I can guarantee that you will enjoy this movie.
RegisterNeutralNeutral
How commonCommon idiomTop 2,000 (common)
CEFR level-B2
Part of speechverb
Collocationsmake a promise, keep a promise, break a promiseabsolutely, personally, constitutionally, be able to, can, be fully guaranteed, absolutely, almost, practically
Antonyms-doubt, uncertainty, dispute
Common mistakesMisinterpreting it as a literal statement about a promise., Using it without context to highlight an agreement.Confused with 'ensure' — 'guarantee' implies a stronger promise., Incorrectly using 'guarantee' without a direct object — always specify what is guaranteed., Mixing up 'guaranteed' as an adjective instead of a past participle.
Usage notesUsed to emphasize the importance of keeping one's word, often in supportive or serious contexts.Use 'guarantee' when you want to express certainty about an outcome. It's suitable for both written and spoken English, but avoid in casual conversations where simpler words like 'promise' may suffice.

See it in real clips

A promise is a promise
Guarantee

Frequently asked questions: A promise is a promise vs Guarantee

What's the difference between A promise is a promise and Guarantee?

A promise is a promise: A promise means you must do what you said. Guarantee: A promise that something will happen or be done.

Which is more common: A promise is a promise and Guarantee?

Guarantee is the most common in everyday English.

Can you show an example of each?

A promise is a promise: When he said he would help me, I knew a promise is a promise. Guarantee: I can guarantee that you will enjoy this movie.

Can I use A promise is a promise and Guarantee interchangeably?

Not always. A promise is a promise and Guarantee 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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