い-Adjくなります — become… (i-adj)

1. Basic structure

2. Main meaning & detailed analysis

• ① Expresses a change in state, feelings, quality, etc.
  Means “to become something” compared to before.
• ② Used to talk about natural changes not directly caused by people.
• The verb “なる” means “to become,” and it combines with the inflected form of adjectives to indicate a process of change.
• Parallel patterns: ・い-Adj → ～くなる
  ・な-Adj → ～になる
  ・Noun → N + になる

3. Illustrative examples

• だんだん寒くなります。
  It gradually gets cold.
• 日本語が上手くなりましたね。
  Your Japanese has gotten better, hasn't it?
• 最近、忙しくなりました。
  Recently, I've gotten busier.
• この道は夜暗くなります。
  This road gets dark at night.
• 子どもが大人しくなりました。
  The child has become more well-behaved.

4. Usage & nuances

• ～くなります is used when describing objective changes (weather, feelings, personality, etc.).
• When you want to express a change brought about by an agent (actively making something become), use ～くします (e.g., 寒くします → make it colder).
• Can be used with degree adverbs such as: だんだん (gradually), もっと (more), 少し (a little).

5. Comparison & distinctions

6. Extended notes

• Often used with time expressions to talk about changes over time: 春になると暖かくなります。 → In spring, it becomes warm.
• In conversation, Japanese speakers sometimes drop “ます” in casual speech: 寒くなったね。 → It's gotten cold, huh.
• This is one of the basic patterns and appears frequently on JLPT N5–N4.

7. Variations & common phrases

• ～くなった：Has become…（寒くなった → has gotten colder）
• ～くなってきた：Has started to become…（暑くなってきた → it's starting to get hot）
• ～くなっていく：Will gradually become…（忙しくなっていく → will get busier and busier）

8. Common mistakes & JLPT traps

• Confusing い → に: ✕ 寒にになります → ○ 寒くなります。
• Confusing it with the active pattern ～くします (to make…): ・寒くなります → it becomes cold (natural). ・寒くします → make it cold (intentional).
• Omitting “く”: ✕ 高いなります → ○ 高くなります。
• JLPT N5 often tests: correctly conjugating “い-Adj → くなります” and distinguishing it from “な-Adj → になります”.