A word or the part of a word that carries the main meaning of other forms is called the root or base. A root can change forms in several ways, such as through conjugation, pluralizing or by adding a prefix or suffix. The meaning of an unfamiliar word can often be determined by identifying the root.
Many words in English have foreign roots, such as the Latin word “ced,” which means “go.” Adding to it can form words such as procedure, recede, secede and intercede. Another Latin root is “ject,” which means “throw.” It creates reject, interject, eject, object, trajectory and so forth.
Conjugated verbs are often different from their base form. Studied and studying are different types of “study.” “Go” is the root of going, gone and went.
These each have a meaning that changes the word it is attached to. “Pre-” means “before” so a prefix comes before the root it is modifying.
Pre-: before; preferential, premium, precursor.
A- and an-: not or without; anarchy, apathy, anonymous
Anti-: against; antiseptic, anti-aging
A suffix comes at the end of a word it modifies.
-En: made of; oaken, silken, woolen
-Er: one who; rancher, driver, minister
-Ful: full of; beautiful, peaceful, bountiful