Cool MateQuickly vs Suddenly
When to use each in English, with meaning, register, and examples.
Quickly
Top 1,000 (very common)A1adverb
Suddenly
Top 1,000 (very common)A2adverb
| Quickly | Suddenly | |
|---|---|---|
| Pronunciation | 🇬🇧 /["/ˈkwɪkli/"]/🇺🇸 /["/ˈkwɪkli/"]/ | 🇬🇧 /["/ˈsʌdənli/"]/🇺🇸 /["/ˈsʌdənli/"]/ |
| Meaning | In a fast manner | Happening quickly and without warning |
| Example | She ran quickly to catch the bus. | I **suddenly realized** what I had to do. |
| Register | Neutral | Neutral |
| How common | Top 1,000 (very common) | Top 1,000 (very common) |
| CEFR level | A1 | A2 |
| Part of speech | adverb | adverb |
| Collocations | move quickly, react quickly, think quickly | suddenly appear, suddenly realize, suddenly stop, suddenly change |
| Antonyms | slowly | gradually, slowly |
| Common mistakes | Using 'quick' instead of 'quickly' when modifying a verb., Placing 'quickly' too far from the verb it modifies., Confusing 'quickly' with 'fastly' since 'fast' is the correct adverb. | 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 | Use 'quickly' when describing how something is done fast. Appropriate in both spoken and written English, but may be overly formal in 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: Quickly vs Suddenly
What's the difference between Quickly and Suddenly?
Quickly: In a fast manner Suddenly: Happening quickly and without warning
Which is more advanced: Quickly and Suddenly?
Suddenly is the highest level, at A2, on the CEFR scale.
Are Quickly and Suddenly the same CEFR level?
Quickly: A1, Suddenly: A2 on the CEFR scale.
What part of speech are Quickly and Suddenly?
Quickly: adverb, Suddenly: adverb.
Can you show an example of each?
Quickly: She ran quickly to catch the bus. Suddenly: I **suddenly realized** what I had to do.
Can I use Quickly and Suddenly interchangeably?
Not always. Quickly 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.