Grammar Info

N5 Lesson 8: 9/13


To become (Adjective)


[な]Adjective + + なる
[い]Adjective[く]+ なる



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About ~になる・~くなる

になる (with な-Adjectives), or くなる (with い-Adjectives) is an expression used in Japanese to show that something is 'becoming (A)'. It can be used with any form of なる, to highlight that something will become (non-past), is becoming (continuous), or has become (past). It can even be used with negative forms, to show that something 'will not become (A)'.

In the example with the tea getting cold, we can see how ている sometimes highlights something that exists in an ongoing state, rather than changing any further. In other words, 'the tea has gotten cold, and remains to be cold'.

Additionally, the adjective いい 'good' is an exception to the regular conjugation rules for い-Adjectives, and will conjugate as よくなる, not いくなる.




    To become difficult.


    To become happy.


    To become fast.


    To become better.


    To become pretty/clean.

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~になる・~くなる – Grammar Discussion

Most Recent Replies (40 in total)

  • Vesicularorb


    Not sure where else to put this. I see in Japanese we use counter words typically as an adverb? And these adverbs seem to function as a noun for connections, ie we use の to connect to a noun after. But what is functionally the difference then between a sentence like 多くの木の公園 where we are describing the trees existing adverbially, vs a sentence like 木が多い公園 where just the い adjective is used plainly?

  • kariforuniajin


    Question about ~くなる conjugation in an example that came up in the とき grammar point.

    The sentence example is:
    “Last night when I got in my futon, I ended up needing to go to the bathroom.”
    How does 「トイレに行きたくなった」translate to “I ended up needing to go to the bathroom.”
    Upon reading it, I would have thought it meant something more like, “Last night when I entered my futon, I didn’t want to go to the bathroom.”

    I’m just wondering what the rules are for conjugating verbs into ~くなる?
    The grammar point in the ~になる・~くなる page does not cover verb conjugations, so I’m a tad confused

  • Fuga


    Hey @kariforuniajin !

    In this sentence, 行く is conjugated using たい to create 行きたい ‘want to go’ and くなる is added to create 行きたくなる ‘I ended up wanting to go to the bathroom’. When the grammar point になる・くなる is attached to a verb conjugated using たい it will follow the conjugation rule of a い-adjective since たい is conjugated in the same way as い-adjectives.

    We hope this clears it up!

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