Cool MateAll of a sudden vs Immediately vs Instantly vs Rapidly
When to use each in English, with meaning, register, and examples.
All of a sudden
Immediately
Instantly
Rapidly
| All of a sudden | Immediately | Instantly | Rapidly | |
|---|---|---|---|---|
| Pronunciation | 🇬🇧 //ɔːl əv ə ˈsʌdən//🇺🇸 //ɔl əv ə ˈsʌdən// | 🇬🇧 /["/ɪˈmiːdiətli/"]/🇺🇸 /["/ɪˈmiːdiətli/"]/ | 🇬🇧 /["/ˈɪnstəntli/"]/🇺🇸 /["/ˈɪnstəntli/"]/ | 🇬🇧 /["/ˈræpɪdli/"]/🇺🇸 /["/ˈræpɪdli/"]/ |
| Meaning | Unexpectedly or very quickly. | right away, without waiting | Right away, without waiting. | quickly or fast |
| Example | All of a sudden, it started to rain heavily. | He answered the question immediately after it was asked. | Her voice is instantly recognizable. | to **increase/spread/expand rapidly** |
| Register | Neutral | Neutral | Neutral | Neutral |
| How common | Top 2,000 (common) | Top 1,000 (very common) | Top 5,000 (fairly common) | Top 1,000 (very common) |
| CEFR level | - | A2 | B2 | B2 |
| Part of speech | adverb | adverb | adverb | |
| Collocations | all of a sudden, a loud noise, all of a sudden, they appeared, all of a sudden, it happened | respond immediately, act immediately, notify immediately | instantly available, instantly recognizable, instantly regret, instantly noticeable | grow rapidly, change rapidly, develop rapidly, increase rapidly |
| Antonyms | gradually, slowly, over time | eventually, later | gradually, slowly, eventually | slowly |
| Common mistakes | Using in overly formal contexts., Confusing with similar phrases like 'suddenly.', Omitting 'of' in the phrase. | Using 'immediate' instead of 'immediately'., Confusing with 'eventually', which means later., Incorrectly placing 'immediately' at the end of a sentence. | Using 'instantly' with past tense incorrectly, e.g., 'I instantly saw' instead of 'I saw instantly'., Confusing it with 'immediately' when the emphasis on speed differs., Forgetting to use it with an action verb. | Using 'rapidly' as an adjective instead of an adverb, Confusing 'rapidly' with 'quickly' in formal writing contexts, Overusing 'rapidly' in informal conversations where simpler words are better |
| Usage notes | Used to describe a change that happens suddenly. Suitable for both spoken and written English; avoid in formal writing. | Use 'immediately' to emphasize urgency or promptness. It's appropriate in both spoken and written English, but avoid in very casual contexts. | Use 'instantly' in both spoken and written English to emphasize immediate action. It's appropriate in most contexts but less common in very casual conversations. | Use 'rapidly' in contexts where something is happening very quickly. It's more formal than 'quickly' and might not be suitable for casual conversations. |
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Frequently asked questions: All of a sudden vs Immediately vs Instantly vs Rapidly
What's the difference between All of a sudden, Immediately, Instantly, and Rapidly?
All of a sudden: Unexpectedly or very quickly. Immediately: right away, without waiting Instantly: Right away, without waiting. Rapidly: quickly or fast
Can you show an example of each?
All of a sudden: All of a sudden, it started to rain heavily. Immediately: He answered the question immediately after it was asked. Instantly: Her voice is instantly recognizable. Rapidly: to **increase/spread/expand rapidly**
Can I use All of a sudden, Immediately, Instantly, and Rapidly interchangeably?
Not always. All of a sudden, Immediately, Instantly, and Rapidly 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.