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originally; primarily
essentially; intrinsically; naturally; by nature; in (and of) itself
proper; rightful; legal; normal
仕事に追われて本来の目的を忘れてはいけない。
We must not forget the original purpose.
スケジュール通りなら本来は彼が来るはずだった。
Originally, he was supposed to come.
調べてみるとこの言葉は本来違う意味で使われていた。
This word originally had a different meaning.