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Using "Beliau" is for someone with high level/status or many people have highly respect to him/her. It's more formal than using "dia".
As Indonesian, When we communicate with other, we prefer Using " Dia" to "beliau".
"Beliau" digunakan untuk hal yang sangat resmi, dan seseorang yang sangat dihormati ataupun kedudukannya tinggi di masyarakat.
"Dia" lebih banyak digunakan untuk percakapan biasa.
