By the way vs Furthermore

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

By the way

Top 2,000 (common)B1

Furthermore

FormalTop 2,000 (common)B2adverb
Most formal: Furthermore
 By the wayFurthermore
Pronunciation🇬🇧 //baɪ ðə weɪ//🇺🇸 //baɪ ðə weɪ//🇬🇧 /["/ˌfɜːðəˈmɔː(r)/"]/🇺🇸 /["/ˌfɜːrðərˈmɔːr/"]/
MeaningAn expression used to add extra information.Also; in addition to what was said before.
ExampleI enjoyed the movie. By the way, did you see the reviews?He said he had not discussed the matter with her. Furthermore, he had not even contacted her.
RegisterNeutralFormal
How commonTop 2,000 (common)Top 2,000 (common)
CEFR levelB1B2
Part of speechadverb
Collocationsby the way, can I add, mention by the way, bring up by the wayfurthermore, it is important, furthermore, we should consider, furthermore, studies show
Antonymsdirectly, mainly, explicitly, primarilyhowever, nevertheless
Common mistakesOmitting it in formal writing., Confusing it with 'in other words'., Using it at the beginning of a sentence.Using 'furthermore' in informal speech too often., Confusing 'furthermore' with 'besides' which can have a different tone., Placing a comma before 'furthermore' incorrectly in sentence structure.
Usage notesUse when introducing an unrelated topic or adding a detail. Avoid in very formal contexts.Use 'furthermore' to add information in formal writing or speech. It's less common in casual conversation. Avoid starting sentences with it in informal contexts.

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By the way
Furthermore

Frequently asked questions: By the way vs Furthermore

What's the difference between By the way and Furthermore?

By the way: An expression used to add extra information. Furthermore: Also; in addition to what was said before.

Which is more formal: By the way and Furthermore?

Furthermore is the most formal of these.

Which is more advanced: By the way and Furthermore?

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

Are By the way and Furthermore the same CEFR level?

By the way: B1, Furthermore: B2 on the CEFR scale.

Can you show an example of each?

By the way: I enjoyed the movie. By the way, did you see the reviews? Furthermore: He said he had not discussed the matter with her. Furthermore, he had not even contacted her.

Can I use By the way and Furthermore interchangeably?

Not always. By the way and Furthermore 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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