Japanese by Example
Learning through examples in manga

Past decision still in effect with 〜ことになっている

ことになっている conveys that preceding action had been decided in the past and still remains in effect. It follows a verb in its plain form or a verb ending in ない.

Further reading

Examples

美少女戦士セーラームーン » Volume 5 » Page 235
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ふだつきのキョーコちゃん » Volume 5 » Page 110
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シャドーハウス » Volume 2 » Page 66
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