He was born profoundly deaf, which means that there's a part of his umwelt that's unavailable to him.
Тѳрѳлхийн сонсголгүй тѳрсѳн бѳгѳѳд түүний "умвэлт"-ийн нэгээхэн хэсэг түүнд  анхнаасаа байгаагүй гэсэн үг.