Eternal vs It could be infinite

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

Eternal

FormalTop 3,000 (common)C1adjective

It could be infinite

Top 3,000 (common)
Most formal: Eternal
 EternalIt could be infinite
Pronunciation🇬🇧 /["/ɪˈtɜːnl/"]/🇺🇸 /["/ɪˈtɜːrnl/"]/🇬🇧 //ɪt kʊd biː ɪnˈfɪnɪt//🇺🇸 //ɪt kʊd biː ˈɪnfɪnɪt//
MeaningLasting forever, never ending.It might not have an end or limit.
ExampleMany religions speak of an eternal life after death.In theory, the universe could be infinite.
RegisterFormalNeutral
How commonTop 3,000 (common)Top 3,000 (common)
CEFR levelC1-
Part of speechadjective
Collocationseternal love, eternal life, eternal flame, eternal damnation, eternal blisscould be infinite, possibilities could be infinite, potential could be infinite
Antonymstemporary, brief, finite-
Common mistakesConfused with 'external', meaning outside., Using 'eternal' to describe short-lived events., Overusing in casual contexts.Confused with 'infinity' as a noun vs 'infinite' as an adjective., Using 'could' when certainty is needed., Misplaced 'be' in the sentence structure.
Usage notesUse 'eternal' in serious or literary contexts. It's appropriate for discussing concepts like love, life, or time but not typically used in casual conversation or everyday situations.Use in contexts discussing possibilities or abstract concepts. Appropriate in casual or formal discussions about limits or possibilities.

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It could be infinite

Frequently asked questions: Eternal vs It could be infinite

What's the difference between Eternal and It could be infinite?

Eternal: Lasting forever, never ending. It could be infinite: It might not have an end or limit.

Which is more formal: Eternal and It could be infinite?

Eternal is the most formal of these.

Can you show an example of each?

Eternal: Many religions speak of an eternal life after death. It could be infinite: In theory, the universe could be infinite.

Can I use Eternal and It could be infinite interchangeably?

Not always. Eternal and It could be infinite 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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