GRAMMAR DETAIL
ことにした
Follows the dictionary or negative form of a verb to express a decision made by the speaker's own will.
Examples
来月から毎朝早く起きることにした。
I decided to get up early every morning starting next month.
Words used
今年は海外旅行をしないことにする。
I have decided not to travel abroad this year.
Words used
Study notes
1. Origins, structure, and basic meaning
- Structure: A verb's dictionary form or
ないform is followed byことにする. - Basic usage:
毎朝早く起きることにしたmeans deciding to get up early every morning.
2. Common pitfalls and similar expressions
- Decision and execution
- In
来月から早く起きることにした, the decision may already be made even though getting up early starts next month. The past tense belongs to the decision.
- In
- Viewpoints with する and なる
参加することにしたforegrounds one's own decision, while参加することになったforegrounds the arrangement or outcome of a decision. The latter alone does not identify exactly who decided.