～ことだ (〜koto da)
Explanation
Expresses advice or recommendation; 'should', 'it is important', 'it is necessary'.
Formation
Verb-ますstem + ことだ, い-Adjective + ことだ, な-Adjective + なことだ, Noun + のことだ
Detailed Explanation
The ～ことだ grammar point is used to express a piece of advice or recommendation to someone. It can be translated as 'should', 'it is important', or 'it is necessary' in English. The formation differs depending on whether it is used with a verb, い-adjective, な-adjective, or noun.
Examples
毎日運動することだ。
Mainichi undou suru koto da.
You should exercise every day.
健康のために、野菜をたくさん食べることだ。
Kenkou no tame ni, yasai wo takusan taberu koto da.
For your health, you should eat lots of vegetables.
勉強しているとき、静かな場所を選ぶことだ。
Benkyou shiteiru toki, shizuka na basho wo erabu koto da.
When studying, you should choose a quiet place.
辞書を使って、新しい言葉を覚えることだ。
Jisho wo tsukatte, atarashii kotoba wo oboeru koto da.
You should use a dictionary to learn new words.
Grammar content sourced from hanabira.org.