Having different registers, the "everyday language", and the "more formal, fancy sounding register", is far from unique to English, and I'd dare-say the majority of broadly used languages have some form of this.
In fact, English has it less than a lot of languages. In Japanese, you not only use different words when in a more formal register, you also conjugate verbs differently and use different honorific suffixes to refer to people. https://en.wikipedia.org/wiki/Honorific_speech_in_Japanese
I guess people who speak japanese can speak 4 languages (casual speech, normal polite desu/masu speech, humble speech, and keigo). They all have different word-choices and conjugations, and there's also similarly a dual-origin story of "some words came from ancient chinese, some from ancient japanese".
Comments
Having different registers, the "everyday language", and the "more formal, fancy sounding register", is far from unique to English, and I'd dare-say the majority of broadly used languages have some form of this.
In fact, English has it less than a lot of languages. In Japanese, you not only use different words when in a more formal register, you also conjugate verbs differently and use different honorific suffixes to refer to people. https://en.wikipedia.org/wiki/Honorific_speech_in_Japanese
I guess people who speak japanese can speak 4 languages (casual speech, normal polite desu/masu speech, humble speech, and keigo). They all have different word-choices and conjugations, and there's also similarly a dual-origin story of "some words came from ancient chinese, some from ancient japanese".