3

According my teacher,

  • ~くする or ~にする is used for direct action, but
  • ~くなる or ~になる is used for indirect action

For me, the meaning of direct and indirect is a bit ambiguous. Consider there is a tool than can cut something. The tool can be either powered by a motor or powered by human energy. Is the decision whether directly or indirectly based on the source of energy to do the action?

I mean the sentence A below will be true if the tool is powered by a motor, for example. Otherwise it will be false if powered by a human.

A: このツールを使うと、ズボンが短くなります。

With almost the same logic, the sentence B below will be true if the tool is powered by a human. Otherwise it will be false if powered by a motor.

B: このツールを使うと、ズボンを短くします。

What do you think? More precisely, when do we have to use する and なる? Any comment is appreciated.

4
  • I'm not quite sure why the motor is important. In either situation the machine is still operated by a person and I'd say the same rules apply to each situation. – ssb Jun 15 '15 at 5:06
  • 2
    このツールを使って、ズボンを短くします。 – Yang Muye Jun 15 '15 at 5:17
  • @ssb: Let's compare scissors and an automatic cutting machine. – Friendly Ghost Jun 15 '15 at 5:18
  • このツールを使うと、ズボンを短くします sounds unnatural. – Chocolate Jun 15 '15 at 6:54
1

A: このツールを使うと、ズボンが短くなります。

If you use ~くなる or ~になる here, you intend to mean this: "If you use this tool, the pants becomes smaller."

B: このツールを使うと、ズボンを短くします。

If you use ~くする or ~にする here, you intend to mean this: "If you use this tool, you make the pants smaller."

As opposed to ~くなる or ~になる, ~くする or ~にする implies that you have made a decision or have made an action yourself.

~くなる or ~になる on the other hand, you're just making a statement or an observation that something has undergone change.

Hope this helps.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.