Cool MateI swear vs Vow
When to use each in English, with meaning, register, and examples.
I swear
InformalTop 2,000 (common)
Vow
FormalTop 3,000 (common)C1verb
Most formal: VowMost common: I swear
| I swear | Vow | |
|---|---|---|
| Pronunciation | 🇬🇧 //aɪ swɛər//🇺🇸 //aɪ swɛr// | 🇬🇧 /["/vaʊ/","/vaʊz/","/vaʊd/","/ˈvaʊɪŋ/"]/🇺🇸 /["/vaʊ/","/vaʊz/","/vaʊd/","/ˈvaʊɪŋ/"]/ |
| Meaning | I promise something is true | A serious promise to do something. |
| Example | I swear I'm telling the truth! | She vowed never to speak to him again. |
| Register | Informal | Formal |
| How common | Top 2,000 (common) | Top 3,000 (common) |
| CEFR level | - | C1 |
| Part of speech | verb | |
| Collocations | swear to tell the truth, swear on my life, swear under oath | quietly, silently, to, vow never to do something, vow revenge, vow revenge against somebody |
| Antonyms | - | break, violate |
| Common mistakes | Using 'swear' without 'I' (like 'swear it's true') - it sounds unnatural., Confusing with 'promise' – 'swear' is stronger and often more emotional., Forgetting to use it only in informal settings. | Confused with 'cow' — they sound similar but have different meanings., Using in informal contexts — 'vow' is too strong for casual promises. |
| Usage notes | Use in casual conversation to emphasize the truthfulness of a statement. It can express strong feelings. Not appropriate for formal contexts. | Use 'vow' when making a serious commitment, often in formal situations like weddings or ceremonies. Avoid in casual conversations. |
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Frequently asked questions: I swear vs Vow
What's the difference between I swear and Vow?
I swear: I promise something is true Vow: A serious promise to do something.
Which is more formal: I swear and Vow?
Vow is the most formal of these.
Which is more common: I swear and Vow?
I swear is the most common in everyday English.
Can you show an example of each?
I swear: I swear I'm telling the truth! Vow: She vowed never to speak to him again.
Can I use I swear and Vow interchangeably?
Not always. I swear and Vow 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.