Guarantee vs I swear on my children

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

Guarantee

Top 2,000 (common)B2verb

I swear on my children

InformalTop 5,000 (fairly common)
Most formal: GuaranteeMost common: Guarantee
 GuaranteeI swear on my children
Pronunciation🇬🇧 /["/ˌɡærənˈtiː/","/ˌɡærənˈtiːz/","/ˌɡærənˈtiːd/","/ˌɡærənˈtiːɪŋ/"]/🇺🇸 /["/ˌɡærənˈtiː/","/ˌɡærənˈtiːz/","/ˌɡærənˈtiːd/","/ˌɡærənˈtiːɪŋ/"]/🇬🇧 //aɪ swɛə(r) ɒn maɪ ˈtʃɪldrən//🇺🇸 //aɪ swɛr ɑn maɪ ˈtʃɪldrən//
MeaningA promise that something will happen or be done.I promise strongly using my children as a reason.
ExampleI can guarantee that you will enjoy this movie.I swear on my children, I will always protect them.
RegisterNeutralInformal
How commonTop 2,000 (common)Top 5,000 (fairly common)
CEFR levelB2-
Part of speechverb
Collocationsabsolutely, personally, constitutionally, be able to, can, be fully guaranteed, absolutely, almost, practicallyswear on my children, strongly swear, promise with sincerity, vow to protect, emphasize with family
Antonymsdoubt, uncertainty, dispute-
Common mistakesConfused 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.Confusion between 'swear on' and 'swear to'., Using in overly formal situations., Incorrectly using with abstract concepts.
Usage notesUse '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.Used in informal contexts to express strong promise or truth, often relates to personal feelings or beliefs.

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Guarantee
I swear on my children

Frequently asked questions: Guarantee vs I swear on my children

What's the difference between Guarantee and I swear on my children?

Guarantee: A promise that something will happen or be done. I swear on my children: I promise strongly using my children as a reason.

Which is more formal: Guarantee and I swear on my children?

Guarantee is the most formal of these.

Which is more common: Guarantee and I swear on my children?

Guarantee is the most common in everyday English.

Can you show an example of each?

Guarantee: I can guarantee that you will enjoy this movie. I swear on my children: I swear on my children, I will always protect them.

Can I use Guarantee and I swear on my children interchangeably?

Not always. Guarantee and I swear on my children 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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