Sign language morphology adds new considerations to well-studied areas, including category identification, inflection vs. derivation, the notions of ideophones, subject, and root, and properties used in lexical classifications. It makes necessary the new notion of reactive effort in understanding how biomechanical factors help shape the lexicon. The prevalence of simultaneity (verticality) over linearity (horizontal temporality) shows that linguistic analysis must include the study of physical properties (visual vs. auditory) if we are to understand language typology. Phonological parameters can have meaning associated with them, either arbitrarily or because they are iconic. This allows for lexical networks that require the mechanism of ion morphs. Certain phenomena are open to analysis as part of a system of visual representation needed in communication; that is, they are gestural and not part of language per se. So the grammar of sign languages covers a more narrow range of phenomena than that of spoken languages.

historically categorized morphological processes under two umbrellas: derivational morphology and inflectional morphology. Derivational morphology is the process American Sign Language (ASL) has grammar just like any other sign language or spoken language. Sign languages are produced in the visual-gestural modality, as opposed to the vocal-auditory modality of spoken languages, which has a unique impact on their grammars . The study of ASL structure dates back to William Stokoe, Dorothy Casterline, and Carl Croneberg in the 1960s. Since then, linguists hav Some linguists have analyzed various compounds as a type of suffixation. Agent nouns may be derived from verbs by adding the sign, or suffix, AGENT and deleting the final hold of the verb, e.g. TEACH+AGENT becoming 'TEACHER'. Superlatives have also been analyzed as created by a formed by suffixation, e.g. SMART+MOST becoming 'SMARTEST'. For example, Ted Supalla's work on ASL verbs of motion analyzed these signs as consisting of many different affixes, articulated simultaneously according to complex grammatical constraints. This differs from the concatenative morphology of many spoken languages, which except for suprasegmental features, such as tone, are tightly constrained by the sequential nature of voice sounds. Numeral incorporation is another derivational morphological process that has been studied in ASL. Certain types of signs, for example, those relating to time and age, may incorporate numbers by assimilating their handshape. For example, the word for 'week' has handshape /B/ with the weak hand and /1/ with the active hand; the active hand's handshape may be changed to the handshape of any number up to 9 to indicate that many weeks. Some linguists have analyzed this phenomenon as a type of affixation. Signs of age, for example, will begin with a touch at the chin. They argue that this touch functions as a prefix which completely assimilates with the handshape of the corresponding age number. For instance, the word for 'nine' is signed with an /F/ handshape produced ipsilaterally in front of the signer's shoulder. The chin-touch in 'nine years old' can be analyzed as an affix, which is then produced with this same /F/ handshape. For 'three years old', however, the prefix is made with a 3 handshape. Fr…

similar morphological expression across a large number of historically unrelated sign languages . Such observations ... realization of some logical variables, sign languages provide a morphological argument for the existence of temporal ... ––, 2008, “ Complex Predicates Involving Events, Time and Aspect: Is This Why Sign Languages Look So Similar ...