Simplify the following text for a Grade 9 native English-speaking person.
Original: The best-known member of this language family , Mongolian ( in Cyrillic orthography as used in Mongolia , Ð Ð 3\/4 Ð 1\/2 Ð Ð 3\/4 Ð '' Ð Ñ Ð '' , and in the vertical Uyghur-derived script as used in Inner Mongolia , China , MongÎ ol Kele ) , is the primary language of most of the residents of Mongolia , and is spoken by around 5.7 million people in Mongolia and China .
Simplified: In Cyrillic orthography as it is used in Mongolia it is written Ð Ð 3\/4 Ð 1\/2 Ð Ð 3\/4 Ð '' Ð Ñ Ð '' , and in the vertical Uygur-derived script as used in it is Inner Mongolia in China it is written MongÎ ol Kele ) . It is the primary language of most of the residents of Mongolia , and is spoken by around 5.7 million people in Mongolia , Russia , and China .