All of a sudden vs Immediately

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

All of a sudden

Top 2,000 (common)

Immediately

Top 1,000 (very common)A2adverb
Most common: Immediately
 All of a suddenImmediately
Pronunciation🇬🇧 //ɔːl əv ə ˈsʌdən//🇺🇸 //ɔl əv ə ˈsʌdən//🇬🇧 /["/ɪˈmiːdiətli/"]/🇺🇸 /["/ɪˈmiːdiətli/"]/
MeaningUnexpectedly or very quickly.right away, without waiting
ExampleAll of a sudden, it started to rain heavily.He answered the question immediately after it was asked.
RegisterNeutralNeutral
How commonTop 2,000 (common)Top 1,000 (very common)
CEFR level-A2
Part of speechadverb
Collocationsall of a sudden, a loud noise, all of a sudden, they appeared, all of a sudden, it happenedrespond immediately, act immediately, notify immediately
Antonymsgradually, slowly, over timeeventually, later
Common mistakesUsing 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.
Usage notesUsed 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.

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All of a sudden

Frequently asked questions: All of a sudden vs Immediately

What's the difference between All of a sudden and Immediately?

All of a sudden: Unexpectedly or very quickly. Immediately: right away, without waiting

Which is more common: All of a sudden and Immediately?

Immediately is the most common in everyday English.

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.

Can I use All of a sudden and Immediately interchangeably?

Not always. All of a sudden and Immediately 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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