Be aware vs Know a thing or two

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

Be aware

Top 2,000 (common)

Know a thing or two

InformalTop 3,000 (common)
Most formal: Be awareMost common: Be aware
 Be awareKnow a thing or two
Pronunciation🇬🇧 //biː əˈwɛə//🇺🇸 //bi əˈwɛr//🇬🇧 //nəʊ ə θɪŋ ɔː tuː//🇺🇸 //noʊ ə θɪŋ ɔr tu//
MeaningKnow about something or be conscious of it.To have some knowledge or experience about something.
ExampleBe aware of your surroundings when walking at night.She knows a thing or two about cooking Italian dishes.
RegisterNeutralInformal
How commonTop 2,000 (common)Top 3,000 (common)
Collocationsbe aware of danger, be aware of changes, be aware of surroundings, be aware of the rulesknow a thing or two about life, know a thing or two about science, know a thing or two about art
Common mistakesConfused with 'aware of' vs 'aware for'., Using it without a subject (e.g., incorrect 'Be aware.' instead of 'You should be aware.').Used in formal contexts where it may sound too casual., Confused with similar idioms but lacks clarity., Overused in situations where specific knowledge should be highlighted.
Usage notesCommonly used in both spoken and written English. Appropriate in most contexts, but avoid in very formal writing.This idiom is best used in casual conversations. Avoid in formal writing or discussions. It's suitable for expressing modest knowledge.

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Be aware
Know a thing or two

Frequently asked questions: Be aware vs Know a thing or two

What's the difference between Be aware and Know a thing or two?

Be aware: Know about something or be conscious of it. Know a thing or two: To have some knowledge or experience about something.

Which is more formal: Be aware and Know a thing or two?

Be aware is the most formal of these.

Which is more common: Be aware and Know a thing or two?

Be aware is the most common in everyday English.

Can you show an example of each?

Be aware: Be aware of your surroundings when walking at night. Know a thing or two: She knows a thing or two about cooking Italian dishes.

Can I use Be aware and Know a thing or two interchangeably?

Not always. Be aware and Know a thing or two 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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