Built from the noun 多く ("many; a lot" — the nominal form of the i-adjective 多い) + の. The resulting phrase functions as an attributive modifier, always placed before a noun.
CORE PATTERN:
多くの + noun = "many [noun]" / "a lot of [noun]"
KEY GRAMMATICAL CONTRAST (important!):
多い and 多くの behave differently:
- 多い is an i-adjective, but it is NOT used attributively before a noun in modern Japanese: *多い人 is unnatural.
- Instead, use 多くの人 to mean "many people."
- Or use 多い as a predicate: 人が多い ("the people are many / there are many people").
So the choice between 多くの and 多い depends on the position:
- Attributive (before noun): 多くの + noun
- Predicate (after noun): noun + が/は + 多い
COMMON COLLOCATIONS:
- 多くの人: many people
- 多くの場合: in many cases
- 多くの時間: a lot of time
- 多くの問題: many problems
- 多くの国: many countries
- 多くの学生: many students
- 多くの企業: many companies
SIMILAR EXPRESSIONS:
- たくさんの: many, lots of — conversational; used with both countable and uncountable nouns. More frequent in speech.
- 大勢の: many (only for people; crowds of people)
- 数多くの: numerous (even more emphatic than 多くの; written)
- 数多: many (literary; somewhat archaic)
- いろんな / 様々な: various (emphasizes variety rather than raw count)
REGISTER:
多くの is the standard written and semi-formal choice. It appears in newspapers, essays, textbooks, speeches, and business writing. In everyday conversation, たくさんの or simply たくさん is more natural.
COMMON MISTAKE:
Learners who start from the adjective 多い often try *多い人 or *多い問題. These are ungrammatical in modern Japanese. Whenever you need to say "many X" as a modifier before a noun, use 多くの + noun.