Roots and Affixes
Aligned to L.4.4 — Common Core State Standards for English Language Arts.
What this lesson teaches
You can unlock unknown words by breaking them into parts. A root carries the main meaning, a prefix adds meaning to the front, and a suffix adds to the end. Many roots come from Greek and Latin. Context clues and a dictionary help too.
Worked examples
Example 1
The word 'unbreakable' splits into 'un-' (not), 'break,' and '-able' (can be). Put together, it means 'not able to be broken' — you figured it out without looking it up.
Example 2
'Biography' is 'bio' (life) + 'graph' (write): a written life. 'Autobiography' adds 'auto' (self) — a life you wrote yourself.
Example 3
Greek and Latin roots repeat constantly in science: 'thermo' (heat) gives thermometer and thermal; 'hydro' (water) gives hydrant and dehydrated.
Practice questions
- Break a word like 'rewrite' into its prefix and root and tell what it means.
- Explain what the prefix 'un-' does to a word.
- Use context clues to guess a hard word, then say how you could double-check it.
Watch the lesson
Every lesson comes with a video taught in English and Spanish — the same video the QR code in the printed workbook opens.
▶ Watch this lessonEn español
Raíces y Afijos
Puedes descifrar palabras desconocidas separándolas en partes. Una raíz lleva el significado principal, un prefijo agrega significado al inicio, y un sufijo agrega al final. Muchas raíces vienen del griego y el latín. Las pistas del contexto y un diccionario también ayudan.
Ejemplo 1: La palabra 'irrompible' se separa en 'i-' (no), 'romp' (romper) y '-ible' (que se puede). Junta, significa 'que no se puede romper' — lo descifraste sin buscarla.
Ejemplo 2: 'Biografía' es 'bio' (vida) + 'grafía' (escritura): una vida escrita. 'Autobiografía' agrega 'auto' (uno mismo) — una vida que tú escribiste.
Ejemplo 3: Las raíces griegas y latinas se repiten sin parar en ciencia: 'termo' (calor) da termómetro y térmico; 'hidro' (agua) da hidrante y deshidratado.
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