MTEL Communication Literacy Skills: Reading Practice Test 2026 - Free Practice Questions and Study Guide

A prefix is defined as a common letter combination that is added to the beginning of a word to alter its meaning. By attaching a prefix to a root word, the meaning of that word can be transformed or specified. For instance, adding the prefix “un-” to the word “happy” changes its meaning to “not happy.” This demonstrates the role prefixes play in modifying the semantic content of a base word.

In contrast, the other options do not accurately describe a prefix. The first choice refers to a suffix, which is added to the end of words, and the second choice describes a root or base word rather than a prefix. The final option mentions a morpheme that cannot stand alone, which applies to prefixes and suffixes (as they typically need to combine with a root word), but it does not capture the essence of what specifically a prefix is.