All of a sudden vs Immediately vs Rapidly vs Suddenly
When to use each in English, with meaning, register, and examples.
All of a sudden
Immediately
Rapidly
Suddenly
| All of a sudden | Immediately | Rapidly | Suddenly | |
|---|---|---|---|---|
| Pronunciation | 🇬🇧 //ɔːl əv ə ˈsʌdən//🇺🇸 //ɔl əv ə ˈsʌdən// | 🇬🇧 /["/ɪˈmiːdiətli/"]/🇺🇸 /["/ɪˈmiːdiətli/"]/ | 🇬🇧 /["/ˈræpɪdli/"]/🇺🇸 /["/ˈræpɪdli/"]/ | 🇬🇧 /["/ˈsʌdənli/"]/🇺🇸 /["/ˈsʌdənli/"]/ |
| Meaning | Unexpectedly or very quickly. | right away, without waiting | quickly or fast | Happening quickly and without warning |
| Example | All of a sudden, it started to rain heavily. | He answered the question immediately after it was asked. | to **increase/spread/expand rapidly** | I **suddenly realized** what I had to do. |
| Register | Neutral | Neutral | Neutral | Neutral |
| How common | Top 2,000 (common) | Top 1,000 (very common) | Top 1,000 (very common) | Top 1,000 (very common) |
| CEFR level | - | A2 | B2 | A2 |
| 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 | grow rapidly, change rapidly, develop rapidly, increase rapidly | suddenly appear, suddenly realize, suddenly stop, suddenly change |
| Antonyms | gradually, slowly, over time | eventually, later | slowly | gradually, 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 '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 | Using 'suddenly' with the wrong tense (e.g., 'sudden' for past actions)., Confusing 'suddenly' with 'sudden', forgetting it needs to modify verbs., Using 'suddenly' too often, making writing sound repetitive. |
| 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 'rapidly' in contexts where something is happening very quickly. It's more formal than 'quickly' and might not be suitable for casual conversations. | Use 'suddenly' to describe an unexpected change or event. Commonly used in storytelling or descriptions of surprising moments. Avoid in very formal contexts. |
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Frequently asked questions: All of a sudden vs Immediately vs Rapidly vs Suddenly
What's the difference between All of a sudden, Immediately, Rapidly, and Suddenly?
All of a sudden: Unexpectedly or very quickly. Immediately: right away, without waiting Rapidly: quickly or fast Suddenly: Happening quickly and without warning
Which is more advanced: All of a sudden, Immediately, Rapidly, and Suddenly?
Rapidly is the highest level, at B2, on the CEFR scale.
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. Rapidly: to **increase/spread/expand rapidly** Suddenly: I **suddenly realized** what I had to do.
Can I use All of a sudden, Immediately, Rapidly, and Suddenly interchangeably?
Not always. All of a sudden, Immediately, Rapidly, and Suddenly 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.