Completely vs Fully

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

Completely

Top 1,000 (very common)A2adverb

Fully

Top 2,000 (common)B2adverb
Most common: Completely
 CompletelyFully
Pronunciation🇬🇧 /["/kəmˈpliːtli/"]/🇺🇸 /["/kəmˈpliːtli/"]/🇬🇧 /["/ˈfʊli/"]/🇺🇸 /["/ˈfʊli/"]/
MeaningTotally or fully.completely or totally
ExampleI completely forgot about the meeting today.I **fully understand** your motives.
RegisterNeutralNeutral
How commonTop 1,000 (very common)Top 2,000 (common)
CEFR levelA2B2
Part of speechadverbadverb
Collocationscompletely agree, completely understand, completely satisfied, completely different, completely unawarefully aware, fully prepared, fully understand, fully loaded, fully engage
Antonymspartially, incompletely, somewhatpartially, incompletely, slightly
Common mistakesUsing 'completely' without a verb or action., Confusing 'completely' with 'totally' in formal contexts., Saying 'completely' in casual situations where simpler words like 'really' might fit better.Using 'fully' in place of 'very' which is not always correct., Confusing 'fully' with 'fill' in terms of spelling., 'Fully' is sometimes misused in contexts where 'entirely' or 'completely' fit better.
Usage notesUse 'completely' to emphasize the totality of an action or state. It's suitable for both spoken and written English but might sound overemphasized in casual conversation.Use 'fully' to emphasize that something is done to the highest degree. Avoid using it in very casual speech where simpler words like 'really' may be preferred.

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Completely

Frequently asked questions: Completely vs Fully

What's the difference between Completely and Fully?

Completely: Totally or fully. Fully: completely or totally

Which is more common: Completely and Fully?

Completely is the most common in everyday English.

Which is more advanced: Completely and Fully?

Fully is the highest level, at B2, on the CEFR scale.

Are Completely and Fully the same CEFR level?

Completely: A2, Fully: B2 on the CEFR scale.

What part of speech are Completely and Fully?

Completely: adverb, Fully: adverb.

Can you show an example of each?

Completely: I completely forgot about the meeting today. Fully: I **fully understand** your motives.

Can I use Completely and Fully interchangeably?

Not always. Completely and Fully 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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