American Sign Language
Phonology
Distinctive features in ASL Each sign in ASL is composed of a number of distinctive components, generally referred to as parameters. A sign may use one hand or both. All signs can be described using the five parameters involved in signed languages, which are handshape, movement, palm orientation, location and non-manual markers. Just as phonemes of sound distinguish meaning in spoken languages, those parameters are the phonemes that distinguish meaning in signed languages like ASL. Changing any one of them may change the meaning of a sign, as illustrated by the ASL signs THINK and DISAPPOINTED:
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