I promise vs Let me say that I swear

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

I promise

Beyond 10,000 (less common)

Let me say that I swear

Top 3,000 (common)
Most common: Let me say that I swear
 I promiseLet me say that I swear
Pronunciation🇬🇧 //aɪ ˈprɒmɪs//🇺🇸 //aɪ ˈprɑːmɪs//🇬🇧 //lɛt mi seɪ ðæt aɪ swɛə//🇺🇸 //lɛt mi seɪ ðæt aɪ swɛr//
MeaningI will do what I say.I promise to tell the truth.
ExampleI promise to help you with your project tomorrow.Let me say that I swear I did not take your pen.
RegisterNeutralNeutral
How commonBeyond 10,000 (less common)Top 3,000 (common)
Collocationsmake a promise, keep a promise, break a promiselet me say that, I swear to tell the truth, I swear I didn't, I swear by it, let me assure you
Common mistakesConfused with 'I promise you' - which adds emphasis., Using it too casually in serious situations.Omitting 'let me say' makes it sound abrupt., Using it in situations that don't require emphasis on truth., Confusing it with 'I promise' which has a different tone.
Usage notesUsed in informal and formal contexts to assure someone of a future action. Avoid in sarcastic tones.Use this phrase to emphasize honesty. Suitable for formal and informal conversations, but avoid in casual contexts.

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I promise
Let me say that I swear

Frequently asked questions: I promise vs Let me say that I swear

What's the difference between I promise and Let me say that I swear?

I promise: I will do what I say. Let me say that I swear: I promise to tell the truth.

Which is more common: I promise and Let me say that I swear?

Let me say that I swear is the most common in everyday English.

Can you show an example of each?

I promise: I promise to help you with your project tomorrow. Let me say that I swear: Let me say that I swear I did not take your pen.

Can I use I promise and Let me say that I swear interchangeably?

Not always. I promise and Let me say that I swear 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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