This document provides a list of common English prefixes, their meanings, and examples. It explains that prefixes are attached to the beginning of words to modify or extend their meaning. Some of the prefixes described include: - Pre-, which means before in time or order. Examples are prehistoric and prepay. - Re-, which means again. Examples are reopen and rethink. - Un-, which means not. Examples are unhappy and unclear. - Over-, which means excessively or completely. Examples are overreact and overjoyed.