〜ことにする

Pattern
〜ことにする
Level
N4
Reading
〜ことにする indicates an active, personal choice made by the speaker. It attaches to the dictionary or negative form of verbs (e.g. 買うことにする, 買わないことにする). It contrasts with 〜ことになる, which indicates a decision made by an external force or circumstances. level: N4, nuance: active decision-making.
Meaning
to decide to do (by one's own will)
Example

健康のために、毎日走ることにしました。 I have decided to run every day for my health.

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