Inflectional and derivational morphology are two key ways languages build and modify words. Inflection adds grammatical info without changing meaning, while derivation creates new words or alters parts of speech. These processes vary across languages, shaping how we express ideas.

Understanding these morphological processes helps us grasp how languages work. Inflection handles grammar, derivation expands vocabulary. Together, they reveal the intricate systems languages use to convey complex meanings through word structure.

Inflectional vs Derivational Morphology

Key Differences

• Inflectional morphology adds affixes to words to express grammatical relationships without changing the word's basic meaning or part of speech
• Derivational morphology adds affixes to create new words or change a word's part of speech, often altering its meaning
• Inflectional morphemes are more productive and regular in application compared to derivational morphemes
• Inflectional morphemes generally occur after derivational ones within a word
• Inflectional morphology becomes obligatory in certain grammatical contexts, while derivational morphology remains optional
• Languages vary in their reliance on inflectional versus derivational morphology for word formation and grammatical expression

Cross-linguistic Variation

• Some languages have extensive inflectional systems (Latin, Russian)
• Other languages have minimal inflection (Mandarin Chinese)
• Inflectional categories differ across languages in number and type
• Derivational processes vary in productivity and semantic predictability between languages
• Morphological typology classifies languages based on their inflectional and derivational characteristics (isolating, agglutinative, fusional)

Functions of Inflectional Morphemes

Grammatical Categories

• Express tense, aspect, mood, person, number, gender, and case
• English inflectional morphemes include plural -s, possessive 's, comparative -er, superlative -est, and verbal inflections -ed, -ing, -s (third person singular)
• Realized as prefixes, suffixes, infixes, or stem changes (ablaut) depending on the language
• Maintain grammatical agreement within sentences (subject-verb agreement, noun-adjective agreement)
• Signal syntactic relationships and affect sentence interpretation through presence or absence
• Interact in complex ways to express nuanced temporal and aspectual meanings (perfect aspect, progressive aspect)

Morphological Realization

• Suffixes (most common in English) (dogs, walked, taller)
• Prefixes (common in Bantu languages for noun class agreement)
• Infixes (found in Tagalog, inserted within the root)
• Stem changes (Germanic strong verbs, sing - sang - sung)
• Suppletion (completely different forms, go - went)
• Zero morphemes (unmarked forms that carry grammatical information)

Word Creation with Derivational Morphemes

Part of Speech Changes

• Change verbs to nouns (teach to teacher, sing to singer)
• Change adjectives to adverbs (quick to quickly, happy to happily)
• Change nouns to adjectives (danger to dangerous, child to childish)
• Change adjectives to verbs (legal to legalize, modern to modernize)
• Create compound words by combining roots (sun + flower = sunflower)

Semantic Alterations

• Add negation (un- in unhappy, non- in nonviolent)
• Intensify meaning (super- in superstar, ultra- in ultramodern)
• Create antonyms (dis- in disagree, anti- in antiwar)
• Form abstract nouns (-ness in happiness, -ity in productivity)
• Indicate diminutives (-let in booklet, -ette in kitchenette)
• Express causative meanings (-ify in simplify, -ize in modernize)

Productivity and Constraints

• Highly productive morphemes easily attach to many bases (-ness, -er)
• Restricted morphemes have limited application (-th as in width, length)
• Phonological changes often accompany derivation (electric to electricity)
• Stress patterns may shift in derived words (photograph to photography)
• Idiomatic meanings can develop, not strictly compositional (understand ≠ stand under)
• Neologisms emerge through derivation to express new concepts (googleable, unfriend)

Analyzing Morphological Structure

Morpheme Identification

• Segment words into constituent morphemes (root/base and affixes)
• Distinguish between free morphemes (can stand alone) and bound morphemes (must attach to other morphemes)
• Identify allomorphs (variant forms of the same morpheme in different environments)
• Recognize non-concatenative processes (reduplication, ablaut, tone changes)
• Account for zero morphemes (unmarked forms carrying grammatical information)

Affix Classification

• Prefixes occur before the root (un-happy, re-do)
• Suffixes occur after the root (hope-ful, teach-er)
• Infixes occur within the root (Tagalog sulat "to write" → sumulat "wrote")
• Circumfixes surround the root (German ge-spiel-t "played")
• Multiple layers of affixation create complex words (un-think-able-ness)

Morphological Challenges

• Fusion combines multiple grammatical categories into a single, indivisible form (Latin amo "I love" expresses person, number, tense, mood)
• Suppletion uses completely different forms for inflection (go → went, be → am/is/are)
• Cranberry morphemes occur only in one or a few words (cran- in cranberry)
• Back-formation creates new words by removing apparent affixes (edit from editor)
• Folk etymology reanalyzes word structure based on misunderstanding (hangnail from agnail)