millions of
fixed phr.. A1 Beginner Oxford
fixed phr.. A phrase used to talk about a very large, non-specific number of people or things.
fixed phr.. a quantifier indicating a very large, indefinite quantity
There are millions of stars in the sky.
Millions of people around the world watched the final match on television.
The archive contains millions of documents, many of which have yet to be digitized or even cataloged by researchers.
Usage
Always precedes a plural countable noun.
Teaching tip
Contrast 'millions of' (indefinite) with specific numbers like 'two million', which do not use 'of' before the noun.
Pitfall
Two millions of people live here.Two million people live here.When a specific number precedes 'million', it stays singular and is not followed by 'of'.