Study guide

7.2 ASL Morphology, Derivational & Inflectional Processes, and Classifier Systems (PDC, SDC, LCC, ICL, BCL)

Boys Town Educational Interpreter Performance Assessment EIPA

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1 Chapter 1: EIPA Overview & Assessment System

EIPA Assessment System: Written Test vs Performance Test, Purpose & State Standards Performance Scoring Rubric (0.0–5.0 Scale), Levels of Competency, and the 3.5 Benchmark Test Administration, Local Test Administrators (LTAs), Scheduling, Accommodations & Retakes

2 Chapter 2: Professional Role, Ethics & Legal Framework

2.1 EIPA Guidelines for Professional Conduct & NAIE Code of Ethics 2.2 Professional Boundaries: The Interpreter vs Teacher, Aide, Tutor, and Friend 2.3 Confidentiality under FERPA, Student Records, and Mandatory Child Abuse Reporting 2.4 Working Conditions, Interpreter Health, and Professional Guidelines: Job Descriptions, Preparation Time, Breaks, and Repetitive Motion Injury

3 Chapter 3: Special Education Law & The IEP Process

3.1 IDEA 2004 Principles: Free Appropriate Public Education (FAPE) and Least Restrictive Environment (LRE) 3.2 The Individualized Education Program (IEP) Team, Accommodations vs Modifications, and Interpreter Input 3.3 Section 504 of the Rehabilitation Act of 1973 and Title II of the Americans with Disabilities Act 3.4 Federal, State, and Local Education Agencies: SEA and LEA Roles, Funding, and State Interpreter Standards 3.5 Educational Assessment and Achievement Testing: Norm-Referenced, Criterion-Referenced, and Intelligence Tests

4 Chapter 4: Classroom Discourse & Educational Dynamics

4.1 Classroom Discourse Structures: Lecture, Teacher-Led Questioning, Group Work, and Peer Interactions 4.2 Educational Settings: Mainstream Classrooms, Resource Rooms, Co-Enrollment, and Residential Schools 4.3 Collaborative Educational Teamwork: Pre-Teaching, Pacing, Lesson Plan Access, and Teacher Communication

5 Chapter 5: Child Cognitive & Psychosocial Development

Piaget's Stages of Cognitive Development in K-12 Learners (Sensorimotor to Formal Operational) Vygotsky's Zone of Proximal Development (ZPD), Scaffolding, and Socio-Cultural Learning Theory Bloom's Taxonomy of Educational Objectives and Erikson's Psychosocial Stages of Development 5.4 Student Development in Practice: Maturity, Autonomy, Calibrating Support, and Understanding vs. Recitation

6 Chapter 6: First & Second Language Acquisition

6.1 Milestones in First and Second Language Acquisition in Deaf and Hard-of-Hearing Children 6.2 The Critical Period Hypothesis, Language Deprivation Syndrome, and Neurological Impacts 6.3 ASL-English Bilingual Development, Visual Language Foundations, and Theory of Mind

7 Chapter 7: Sign Language Linguistics & Structure

7.1 ASL Phonology: The Five Parameters (Handshape, Movement, Location, Orientation, Non-Manuals) 7.2 ASL Morphology, Derivational & Inflectional Processes, and Classifier Systems (PDC, SDC, LCC, ICL, BCL) 7.3 ASL Syntax: Topic-Comment Structure, Spatial Referencing, Indexing, and Non-Manual Signals

8 Chapter 8: Signed Systems & Visual Communication Modes

8.1 ASL vs Manually Coded English: History, Linguistic Status, and Educational Rationale 8.2 Signing Exact English (SEE II): Principles, Affixes, Morpheme Inventions, and Classroom Use 8.3 Contact Sign / PSE / CASE, Cued Speech Mechanics, and the Rochester Method

9 Chapter 9: English Language Competency for Interpreters

9.1 English Syntax and Grammatical Structures Relevant to K-12 Interpreting 9.2 Academic Vocabulary Acquisition in STEM, Social Studies, and English Language Arts 9.3 Idioms, Metaphors, Figurative Language, and Register Levels in Educational Contexts

10 Chapter 10: Literacy Development & Reading Instruction

10.1 Reading Development Models: Phonics vs Whole Language vs Balanced Literacy for Deaf Students 10.2 Visual Phonics, Chaining, Fingerspelling, and Print-to-Sign Mapping Strategies 10.3 Tutoring Guidelines for Educational Interpreters: Scope, Teacher Supervision, and Instructional Integrity

11 Chapter 11: Deaf Culture & Cultural Identity

11.1 Core Values, Traditions, Collectivism, and Key Historical Milestones of the American Deaf Community 11.2 Audism, Linguistic Hegemony, and Deaf Identity Development Models in School-Age Youth 11.3 Diversity in Deaf Education: Deaf Students of Color, DeafBlind Students, and Hearing Family Dynamics

12 Chapter 12: Technology & Medical Aspects of Deafness

12.1 Anatomy of the Auditory Mechanism, Etiologies, and Types of Hearing Loss 12.2 Reading and Interpreting Audiograms, Decibels, Hertz, Speech Banana, and Classroom Acoustics 12.3 Hearing Aids, Cochlear Implants, Bone-Anchored Systems, FM/DM Systems, and Captioning / CART 12.4 Deaf Community Access Technology: Relay Services, TTY, VRS, VCO, Text Devices, Alerting Systems, and Captioned Media

13 Chapter 13: Interpreting Process & Discourse Mapping

13.1 Cognitive Models of Interpreting (Cokely, Colonomos, Seleskovitch) and Décalage / Processing Time 13.2 Message Equivalence, Omission, Addition, Substitution, and Anomaly Analysis in K-12 Interpreting 13.3 Sight Translation of Educational Materials, Test Interpreting Protocols, and Educational Transliteration 13.4 Role Models of Interpreting: Helper, Conduit, Bilingual-Bicultural, Ally, and the Educational Team Member

14 Chapter 14: EIPA Performance Test Mastery & Diagnostic Skills

14.1 Voice-to-Sign Mastery: Message Cohesion, Spatial Mapping, Role Shift, and Conceptual Accuracy 14.2 Sign-to-Voice Strategies: Receptive Analysis of Immature, Idiosyncratic, and Diverse Student Signing 14.3 Diagnostic Feedback Analysis, Professional Growth Plans, EIPA Mentorship, and Achieving a 3.5+ Rating

7.2 ASL Morphology, Derivational & Inflectional Processes, and Classifier Systems (PDC, SDC, LCC, ICL, BCL)

Key Takeaways Explain This Topic AI

ASL morphology operates through both free morphemes (independent lexical roots like CAT or SIT) and bound morphemes (affixes such as the agentive PERSON-MARKER, directional inflections, and aspectual contours).

Derivational morphology alters lexical meaning or syntactic category, exemplified by Supalla & Newport's noun-verb pairs: nouns display small, repeated, restrained/doubled movement (CHAIR, AIRPLANE), whereas verbs display single, continuous movement (SIT, FLY-TO).

Numeral incorporation embeds numbers 1 through 9 directly into base time roots (hours, days, weeks, months, years, age), while numbers 10 and above require a separate two-sign sequential construction.

Verbs inflect for temporal aspect through modified movement dynamics: uninflected (base), habitual (rapid, repeated circular), continuous/durative (slow, smooth, elongated circular), iterative (repeated sharp stops), and intensive (rapid onset, freeze, sharp release).

Classifier predicates (classifier constructions) categorize physical entities and spatial dynamics across six core types: Descriptive (DCL/SASS), Semantic/Predicate (SCL/PDC), Locative (LCL), Instrument (ICL), Body (BCL), and Bodypart (BPCL).

Last updated: September 2026

7.2 ASL Morphology, Derivational & Inflectional Processes, and Classifier Systems (PDC, SDC, LCC, ICL, BCL)

Quick Answer: Morphology is the study of word structure and the meaningful units (morphemes) that construct lexical items. In ASL, morphology operates both sequentially (compounding) and simultaneously (layering movement and spatial inflections onto root signs). Derivational morphology creates new words or transforms parts of speech—most notably demonstrated in noun-verb pairs (Supalla & Newport 1978), where nouns utilize small, repeated, restrained/doubled movement ( CHAIR , FOOD , AIRPLANE ) and verbs utilize single, continuous movement ( SIT , EAT , FLY-TO ). Numeral incorporation permits numbers 1 through 9 to bind directly into time roots, while numbers 10 and above require two separate signs. Temporal aspect inflections modify verb movement contours to depict habitual, continuous, iterative, or intensive action. Finally, classifier predicates (DCL, SCL/PDC, LCL, ICL, BCL, BPCL) provide a sophisticated morphological system for depicting spatial relationships, motion, and complex STEM concepts in K-12 classrooms.

1. Bound vs. Free Morphemes in Visual-Gestural Languages

A morpheme is the smallest meaningful unit of language. In ASL linguistics, morphemes are categorized into two fundamental types:

1. Free Morphemes

Definition: Meaningful linguistic units that can stand completely alone as independent words without requiring attached affixes.

Examples: Root signs such as CAT , TEACH , RUN , BOOK , TRUE , SIT , BLUE , HOUSE .

2. Bound Morphemes

Definition: Meaningful units of language that cannot stand alone ; they must attach to a root morpheme to convey grammatical or lexical meaning.

ASL Bound Morpheme Types:

The Agentive Suffix ( PERSON-MARKER ): Derived from the sign PERSON (two flat hands moving downward along the sides of the torso). When affixed to a verb root, it derives an occupational noun: TEACH + PERSON-MARKER = TEACHER ; LAW + PERSON-MARKER = LAWYER ; MANAGE + PERSON-MARKER = MANAGER ; SCIENCE + PERSON-MARKER = SCIENTIST .

Directional Inflections: Path movements marking subject and object bound directly to agreement verbs ( GIVE , HELP , INFORM ).

Temporal Aspect Contours: Circular, elongated, or repeated movement paths bound to verb stems.

Numeral Handshapes: Numeric hand configurations (1–9) bound directly into time roots.

Negative Incorporation: A bound outward twisting movement accompanied by a headshake affixed to specific stative verbs: KNOW → DON'T-KNOW ; WANT → DON'T-WANT ; LIKE → DON'T-LIKE .

2. Derivational Morphology: Noun-Verb Pairs and Compound Formation

Derivational morphology creates new lexical items, alters core semantic meaning, or changes a sign's grammatical category (e.g., transforming a verb into a noun): [ ASL Derivational Morphology ]

  • |
  • +--------------------------+--------------------------+
  • | |
  • [ Noun-Verb Pairs ] [ Compound Formation ]
  • (Supalla & Newport 1978) (Klima & Bellugi 1979)
  • | |
  • Shared Handshape, Location, ORI • Two distinct roots merge
  • NOUN: Small, repeated, restrained doubled motion • 1st sign hold deleted
  • VERB: Single, continuous or larger motion • Movement epenthesized & reduced
  • (e.g., CHAIR vs. SIT; FOOD vs. EAT) • Non-compositional new meaning
  • (e.g., FACE+NEW = STRANGER)
  • Noun-Verb Pairs (Supalla & Newport 1978)

In their landmark study, linguists Ted Supalla and Elissa Newport demonstrated that ASL possesses hundreds of semantically related noun-verb pairs that share identical handshapes, locations, and palm orientations, but are systematically distinguished by movement dynamics :

Nouns: Articulated with small, repeated, restrained, or doubled movements .

Verbs: Articulated with a single, continuous, directional, or larger movement .

Matrix of High-Frequency Noun-Verb Pairs

Concept Pair Shared Parameters (Handshape, Location, ORI) Noun Movement (Small, Repeated, Restrained) Verb Movement (Single, Continuous, Dynamic)

CHAIR / SIT Bent 'U'/'H' hands; neutral space; palms down Small, repeated downward tap Single downward contact onto fingers

AIRPLANE / FLY-TO 'I-L-Y' handshape; neutral high space; palm down Double, short forward pulses Single, long, continuous forward glide

FOOD / EAT Flat-O handshape; mouth location; palm in Double tap of fingertips to lips Single insertion movement to mouth

DOOR / OPEN-DOOR Flat 'B' hands; neutral chest space Double small swinging motion Single outward swinging motion

TELEPHONE / CALL 'Y' handshape; ear location; palm in Double small tap against ear Single outward arc toward addressee

SCISSORS / CUT 'V' handshape; neutral space; palm out Double snip of index/middle fingers Single or continuous slicing forward

WINDOW / OPEN-WINDOW Flat 'B' hands; chest space; palms in Double small up-and-down bounce Single upward sliding motion

CAR / DRIVE Modified 'S' fists; chest space; palms in Small, double steering shake Single forward steering push

The Noun-Verb Trap on the EIPA Exam

On the EIPA Performance Test, educational interpreters are frequently penalized for producing nouns when the classroom teacher gives action commands. If a 1st-grade teacher announces, "Class, please sit down on the carpet," and the interpreter produces a double tapping motion ( CHAIR ), the interpreter has committed a morphological error, signing "Class, please chair on the carpet." Precision in movement dynamics is critical for maintaining grammatical fidelity.

ASL Compound Formation Rules (Klima & Bellugi 1979)

When two independent free roots combine to form a compound noun, the signs undergo four systematic morphological transformations:

First Hold Deletion: The static hold at the end of the initial sign is deleted so movement does not stop.

Movement Epenthesis and Reduction: The independent movements of both signs are shortened and bridged by a single fluid transition.

Assimilation: Handshapes or palm orientations anticipate or assimilate across the boundary.

Semantic Specialization (Idiomaticity): The meaning of the compound becomes non-compositional (the compound means something distinct from the sum of its parts):

  • FACE + NEW = STRANGER
  • THINK + SAME = AGREE
  • BLUE + SPOT = BRUISE
  • TALK + NAME = REPUTATION
  • SLEEP + SUNRISE = OVERSLEEP
  • PARENTS (from MOTHER + FATHER contracted into a single chin-to-forehead sweep)
  • 3. Numeral Incorporation and Morphological Constraints

Numeral incorporation is an inflectional morphological process where an independent numerical morpheme is bound directly into a base root sign, simultaneously conveying both the lexical concept and the exact quantity:

Mechanics of Numeral Incorporation

The root sign provides the location, movement path, and orientation .

The numeral provides the handshape (replacing the root sign's default handshape).

Eligible Root Families: HOUR , DAY , WEEK , MONTH , YEAR , MINUTE , AGE (flick off chin), TIME / O'CLOCK (tap on wrist), DOLLAR , RANK / LISTING (counting on non-dominant fingers).

The Universal Rule of 1–9 vs. 10+

Quantities 1 through 9: Can be incorporated directly into the root sign:

3-WEEKS : '3' handshape moves forward across the non-dominant base palm.

5-YEARS-OLD : '5' handshape flicks downward from the chin.

2-HOURS : '2' handshape circles the non-dominant palm.

4-MONTHS : '4' handshape moves downward along the non-dominant index finger.

7-DOLLARS : '7' handshape twists outward from neutral space.

Quantities 10 and Above: Numeral incorporation is morphologically and phonologically blocked . Because handshapes for numbers 10 and above involve complex internal movements (wiggling, shaking, or thumb flicking), attempting to merge them into a base root exceeds visual-motor constraints.

Classroom Rule: For numbers 10 and above, the signer must produce a two-sign sequential construction : first the numeral sign, followed immediately by the independent base sign:

Correct: 10 followed by WEEK ; 12 followed by YEAR ; 15 followed by HOUR .

Ungrammatical: Attempting to execute a '10' fist or '12' flick while tracing the path of WEEK or YEAR .

4. Temporal Aspect Inflections on Verbs

Unlike English, which relies on bound tense suffixes ( -ed ) and auxiliary verbs ( "has been studying" ), ASL verbs do not mark past, present, or future through affixes. Instead, ASL establishes tense through sentence-initial temporal adverbs ( YESTERDAY , PAST , FUTURE ).

However, ASL verbs possess an exceptionally rich system of temporal aspect inflections (Klima & Bellugi 1979). Aspect conveys how an action unfolds over time —its duration, frequency, repetition, or intensity—by modifying the verb's movement contour, rhythm, and accompanying facial markers:

Aspectual Inflection Categories

Aspect Category Movement Contour & Dynamics Facial Non-Manual Marker Semantic Value in English Classroom Context Example

Uninflected (Base) Single, standard linear path Neutral expression Simple action: "to study" , "to look" "He will study tonight."

Habitual Repeated, rapid, rhythmic circular or elliptical motions Relaxed or "mm" mouth shape Regular, customary occurrence: "studies habitually" "The student studies every single day."

Continuous / Durative Slow, elongated, steady, unbroken circular motion Concentrated expression; pursed lips or slight squint Sustained action over time: "studying continuously for hours" "She sat studying all afternoon without stopping."

Iterative Repeated sharp thrusts with abrupt stops and resets Tense cheeks, furrowed brow Repeated action with pauses: "studies again and again with interruptions" "He kept returning to study, stopping and starting over."

Intensive Rapid onset, sudden frozen hold with tension, sharp release Clenched teeth, squinted eyes, tense neck Acute effort or extreme degree: "crams intensely" , "super fast" "The senior crammed frantically right before the AP exam."

5. Classifier Predicates: The Taxonomy of Depicting Signs

In ASL linguistics, classifier predicates (also termed depicting signs or classifier constructions ) represent one of the most expressive, morphologically complex domains of visual language. A classifier predicate combines a classifier handshape (which represents an entire category or class of nouns sharing physical characteristics) with spatial location, movement trajectory, and orientation morphemes : [ ASL Classifier Taxonomy ]

  • |
  • +---------------+----------------+----------------+---------------+---------------+
  • | | | | | |
  • [ DCL ] [ SCL / PDC ] [ LCL ] [ ICL ] [ BCL ] [ BPCL ]
  • Descriptive Semantic / Pred Locative Instrument Body Classifier Bodypart
  • Contour, shape, Class of entity; Spatial position Manipulation Upper body acts Specific limbs
  • texture, size motion & path & arrangement of tool/object as referent (feet, ears)
  • (DCL:B, DCL:C) (CL:3, CL:1) (LCL:B, LCL:55) (ICL:scissors) (BCL:flail) (BPCL:feet)
  • 1. Descriptive Classifiers (DCL) / Size and Shape Specifiers (SASS)

Function: Describe the physical contours, geometric dimensions, textures, surface patterns, and shapes of objects.

Examples:

DCL:B (flat, smooth surface; desktop; sheet of metal).

DCL:C (thick circular column, massive tree trunk, cylindrical beaker).

DCL:G (thin wire, slender stripe, narrow border).

DCL:44 (striped pattern, grid lines, vertical fence slats).

2. Semantic Classifiers (SCL) / Predicate Classifiers (PDC)

Function: A specific handshape functions as a pro-form representing an entire semantic class of entities, depicting the entity's path, velocity, orientation, and spatial displacement through space.

Examples:

CL:3 (vehicles: cars, trucks, buses, bicycles, boats navigating terrain or colliding).

CL:1 (upright human being walking, slender pole falling, individual standing).

CL:V / bent-V (two-legged human walking, seated individual, crouched animal jumping).

CL:C (cup, bowl, or thick container moving or being set down).

3. Locative Classifiers (LCL)

Function: Depict the precise spatial position, static location, or spatial relationship between two or more entities in signing space.

Examples:

LCL:B (placing a book onto a specific high shelf).

LCL:55 (a circular arrangement of student desks, or an orchard of trees situated along a winding river).

4. Instrument Classifiers (ICL)

Function: The signer's hands represent the human hands of an agent holding, manipulating, operating, or interacting with a physical tool or instrument.

Examples:

ICL:holding-scissors (cutting along a curved line).

ICL:holding-pipette (squeezing drops into a test tube in chemistry).

ICL:turning-key (inserting and twisting a key in a lock).

ICL:holding-steering-wheel (driving a vehicle around sharp curves).

5. Body Classifiers (BCL)

Function: The signer's entire upper torso, shoulders, and head enact the physical posture, actions, movements, or emotional demeanor of a character or animal.

Examples:

BCL crossing arms defensively and tapping a foot in impatience.

BCL cowering, trembling, and shielding the face in fear.

BCL puffing out the chest and strutting forward arrogantly.

6. Bodypart Classifiers (BPCL)

Function: The signer's hands represent specific anatomical body parts (typically feet, legs, or animal features) of an entity, rather than the entire body.

Examples:

BPCL:B (two flat hands representing feet walking, stomping, or tapping rhythmically).

BPCL:bent-V (two bent fingers representing animal ears twitching or dog paws digging).

BPCL:1 (two index fingers representing eyes shifting nervously back and forth).

6. Communicating Technical and Scientific STEM Concepts with Classifiers

In K-12 educational interpreting, particularly in middle and high school STEM subjects (biology, chemistry, earth science, physics), instructors constantly explain dynamic physical mechanisms that lack direct lexical sign translations. Attempting to fingerspell every English word (e.g., fingerspelling "subduction" , "mitosis" , "evaporation" ) creates rapid cognitive overload and deprives the deaf student of conceptual understanding.

Master educational interpreters employ the evidence-based Label-Then-Depict Model :

Label: State the conceptual English term through fingerspelling and standard sign vocabulary (e.g., fingerspell M-I-T-O-S-I-S and point to the printed word on the board).

Ground: Establish the physical entities in signing space using classifier handshapes.

Depict: Utilize dynamic classifier predicates to illustrate the mechanical process visually:

STEM Classifier Case Studies

Plate Tectonics & Continental Subduction (Earth Science):

Non-dominant hand: CL:B representing the dense oceanic plate.

Dominant hand: CL:B representing the continental plate.

Interaction: The dominant plate collides with the non-dominant plate; the non-dominant plate slides downward into the mantle ( subduction ), while the dominant plate buckles upward ( CL:bent-5 depicting mountain range uplift and volcanic activity).

Cellular Mitosis & Division (Biology):

Two curved hands ( CL:C facing each other) form a single spherical cell.

The chromosomes align at the equator ( DCL:X interlocked).

The cell elongates and pinches in the middle; the two hands separate into two distinct spherical cells ( two separate CL:C shapes ), visually demonstrating cytokinesis.

Hydrologic Water Cycle (Environmental Science):

LCL:B represents the ocean surface; CL:5 wiggles upward with furrowed brows depicting evaporation; DCL:C masses in upper signing space for cloud condensation; CL:5 inverted moves downward with rapid tapping for precipitation; CL:B angles downward for groundwater runoff.

  • 7. Realistic K-12 Classroom Scenarios
  • Scenario A: 2nd-Grade English Language Arts Reading Lesson

The teacher conducts a guided reading lesson: "Look at the picture on page 14. The girl sits down on the chair, then opens her book to read."

Student Signing Analysis: When summarizing the page, an 8-year-old deaf student signs: GIRL CHAIR [double tap], SIT [single contact], BOOK [double tap] OPEN-BOOK [single sweep], READ.

Linguistic Precision: The student accurately differentiates the derivational noun-verb pairs: CHAIR (double tap) vs. SIT (single contact), and BOOK (double tap) vs. OPEN-BOOK (single sweep). The educational interpreter voices the student's summary with total grammatical fidelity: "The girl sits in her chair, opens her book, and reads."

Scenario B: 8th-Grade Physical Science Lab on Levers

The teacher demonstrates mechanical advantage using a fulcrum, wooden board, and heavy brick: "When we push down on the long end of the lever, the fulcrum redirects the force, lifting the heavy load upward with minimal effort."

Interpreter Classifier Deployment:

The interpreter sets up a CL:1 pointing upward on the non-dominant hand as the fulcrum.

The dominant hand places a flat CL:B horizontally across the fulcrum as the lever board.

A heavy brick is placed on one end ( CL:C heavy).

The interpreter uses an Instrument Classifier ( ICL:push-down ) on the opposite long end; the CL:B pivots on the CL:1 fulcrum, elevating the CL:C load effortlessly.

Educational Outcome: The deaf student immediately grasps the mechanical physics concept because the interpreter converted abstract auditory physics terminology into an accurate, three-dimensional spatial classifier model.

8. Exam Traps & Strategic Distinctions

Trap 1: Producing Noun-Verb Pairs with Identical Movement Dynamics. EIPA raters specifically evaluate whether an interpreter produces nouns with small, repeated, restrained movement and verbs with single, continuous movement. Failing to maintain this distinction represents a significant morphological deficiency.

Trap 2: Attempting Numeral Incorporation for Numbers 10 and Above. Candidates often attempt to incorporate numbers like 10, 12, or 20 into base signs like WEEK or YEAR . Remember that numeral incorporation is strictly blocked for quantities 10 and above; always produce the number first, followed by the base sign.

Trap 3: Confusing Instrument Classifiers (ICL) with Bodypart Classifiers (BPCL). An ICL shows how human hands manipulate an external object (e.g., holding a steering wheel or scissors). A BPCL represents the body part itself acting as an anatomical entity (e.g., two fingers representing an animal's legs jumping).

Loading diagram... ASL Morphological Systems and Classifier Predicate Taxonomy