The English writing system is based not only on sound but also on meaning. Morphological knowledge refers to the understanding of how morphemes can be used to form words. A morpheme is the smallest unit of meaning within words, including prefixes, suffixes, and bases. All words are made up of one or more morphemes. Students apply their consolidated phonological awareness and phonics knowledge, as well as their developing orthographic and morphological knowledge, to read and spell words in isolation and in various text contexts. Words consist of bases that convey meaning and that can be modified with affixes (prefixes and suffixes) to change the meaning of the word. Adding prefixes and/or suffixes may have three other impacts on the resulting words:
Students develop an understanding of morphology when they are introduced to word meanings, first just the base which is the main unit of meaning, i.e., cup. When they are introduced to prefixes and or suffixes, i.e., the plural -s for cups, students learn that the meaning of the word is changed with the addition of the affix. The English language is layered, reflecting the accumulation of historical influences. Early readers and writers learn Anglo-Saxon words; these are typically short, single-syllable words for common, everyday things. As students build more morphological knowledge, they learn Latin/Romance words. These are typically multisyllabic with prefixes, bases, and suffixes that are used across content areas. Older students develop proficiency with Greek combining forms, units of meaning that are typically found in subject-specific texts.
Beginning to use suffixes, including: –s, –es, –ed, –ing
Recognizing that some suffixes can be pronounced in different ways (e.g., –s can be /s/ as in “cats” and /z/ as in “dogs”)
Orally working with groups of words with the same base (e.g., play, playing, playdate)
Recognizing affixes in oral or written language
Recognizing compound words during oral activities
Using prefixes, including: pre–, de–, a– (schwa), co–, uni–, bi–, tri–, mis–, dis–
Using suffixes, including: –ion, –ure, –er, –or, –ist, –ish, –y, –ness, –less, –able/ –ible, –ful
Understanding that derivational affixes not only change the meaning of the word, but also can change the part of speech
recognizing that as affixes are added, pronunciation may shift
Adjusting syllable stress and schwa to produce the correct pronunciation
Exploring derivational word families while adding affixes to a learned base (e.g., changing a verb to a noun: instruct + ion = instruction)
Using prefixes, including: trans–, post–, inter–, intra–, over–, under–, sub–, non–, in–/im– (in/into), anti–, mid–
Using suffixes, including: –ic, –al/–ial, –ous, –ive
Using adverbs (e.g., recognizing and using suffixes to form adverbs that describe a specific manner, period of time, or order: –y, –ly, –ful, –less)
Recognizing and using bound bases
Understanding how words move across grammatical boundaries depending on their use and context (e.g., The students enjoyed their success (noun). → The successful (adjective) student aced the test. → We are successful (adjective). → She successfully (adverb) climbed the mountain.)
Using derivational families to support spelling words with a schwa sound (e.g., students can use define to choose a grapheme for the schwa in definition)
Using prefixes, including: fore–, super–, semi–, en–/em–
Using suffixes, including: –ant, –ent, –ate, –ism
Understanding how words move across grammatical boundaries depending on their use and context (e.g., The students enjoyed their success (noun). → The student was successful (adjective) and passed the test. → We are successful (adjective). → She successfully (adverb) climbed the mountain.)
Using derivational families to support spelling words with a schwa sound (e.g., students can use define to choose a grapheme for the schwa in definition)
Morphology plays a critical role in both reading and writing. Research indicates that morphology instruction has consistent positive impacts on students’ word reading (Carlisle, 2010). Morphology supports vocabulary, a critical component of reading comprehension.
Understanding the meaningful units of language allows students to also understand the grammatical roles of words. Since morphemes are used to convey meaning, strong morphological knowledge supports students in making meaning of texts across a wide variety of contexts and domains.
In writing, the spelling of morphemes is typically stable and consistent. An understanding of morphology supports written composition, as students must account for the fact that spelling is based not only on a word’s sound, but also on its meaning (Rastle, 2019).
Students should be taught that words are composed of meaningful parts. Starting students out with the idea of a base is one of the simplest methods to build morphological knowledge. A base is an English word in its most basic form that can have prefixes and suffixes (affixes) added to modify its usage or meaning.
Generally speaking, morphology instruction should be explicit, involving direct instruction of prefixes, suffixes, and bases. Students should learn the pronunciation, spelling, and meaning of these units of language.
Early morphology instruction should focus on inflectional suffixes. These are endings, including -ed, -s, -ing, that don’t change a word’s part of speech, but instead signal a change in tense or number, a comparison, or possession.
As students build more understanding of morphology, they can be explicitly taught additional prefixes, bases, and suffixes. This may be especially helpful in junior, intermediate, and senior grades when phonics instruction has stopped. As words get longer and more complex, phonics and phonemic awareness are no longer fully sufficient to read, spell, and understand words. With morphology instruction, students are able to meaningfully explore the pronunciation, spelling, and meaning of complex words across a variety of content-specific texts.
“The primary purpose of assessment is to improve student learning.”
Growing Success: Assessment, Evaluation and Reporting in Ontario Schools, 2010, p. 28
A variety of sources of insight into students’ application of morphological knowledge can be used as assessment for learning to drive evidence-based explicit and systematic instruction.
Assessing students’ knowledge, understanding, and application of morphology can be measured through reading and writing assessments. Oral Reading Fluency screeners (ORF), typically included in early reading screening, tend to include words with affixes.
In writing, consider using a spelling inventory for assessment for learning. These tools can typically be administered whole class with a list of words. Students’ spelling is scored with a scoresheet that allows for a close examination of their understanding of sounds, spelling patterns, and morphology.
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