Oh brother vs Really

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

Oh brother

InformalBeyond 10,000 (less common)

Really

Top 1,000 (very common)A1adverb
Most formal: ReallyMost common: Really
 Oh brotherReally
Pronunciation🇬🇧 //əʊ ˈbrʌðə//🇺🇸 //oʊ ˈbrʌðər//🇬🇧 /["/ˈriːəli//ˈrɪəli/"]/🇺🇸 /["/ˈriːəli/"]/
MeaningA way to express frustration or annoyance about something.very or truly
ExampleOh brother, I can't believe I forgot my keys again!I really enjoy going to the beach.
RegisterInformalNeutral
How commonBeyond 10,000 (less common)Top 1,000 (very common)
CEFR level-A1
Part of speechadverb
Collocationsoh brother, not again, oh brother, seriously, oh brother, come onreally want, really good, really sure, really excited, really important
Antonyms-seldom, never
Common mistakesUsed as a greeting instead of an expression of frustration., Mispronounced as two separate words instead of a chunk., Used in overly formal contexts.Using it in place of 'real' when describing a noun., Confusing it with 'really' in terms of degree, e.g., 'really good' instead of 'very good'.
Usage notesUsed when surprised or exasperated by a situation. It's often casual and used among friends or family, but can be seen as unprofessional in formal settings.Used to emphasize an adjective or another adverb. It can be informal in casual conversations but is accepted in most contexts; avoid overusing it in formal writing.

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Oh brother
Really

Frequently asked questions: Oh brother vs Really

What's the difference between Oh brother and Really?

Oh brother: A way to express frustration or annoyance about something. Really: very or truly

Which is more formal: Oh brother and Really?

Really is the most formal of these.

Which is more common: Oh brother and Really?

Really is the most common in everyday English.

Can you show an example of each?

Oh brother: Oh brother, I can't believe I forgot my keys again! Really: I really enjoy going to the beach.

Can I use Oh brother and Really interchangeably?

Not always. Oh brother and Really 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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