But abstract concepts, professional terminology, and proper nouns are harder to express in natural signs and require supplementation from character signs. If the hearing impaired wish to learn something technical or engage in deeper analytic thinking, they must rely on character signs.
不過，抽象的詞彙、概念或人名、地名等專有名詞，較難用自然手語表現，一開始必須靠文字手語輔助；聽障者若想學習專業知識，或是做更深度的邏輯思考，也需要仰賴文字手語。