BU Center for the Assessment of Sign Language Interpretation (CASLI) Practice Test

Casual (informal) register is the everyday, relaxed way people talk when they’re with family or friends. It uses natural, conversational language, common slang or slangy phrases, shorter sentences, and contractions. It feels friendly and personal because it assumes shared context, so it doesn’t aim for precision or formality. This is different from language used in very formal settings, which is careful, distant, and polished; legal documentation language, for example, sticks to precise terms to avoid ambiguity; scientific or technical language uses specialized jargon that isn’t part of everyday talk. So the description that best fits casual register is the one about language frequently used among family and between friends.