A dictionary sure is helpful in finding out the meaning of words that we do not know. However, it is not something that we have on hand all of the time. To be able to at least guess the meaning of a new word, it is very helpful to know how to identify root words and the meaning of common affixes. Root words are also known as base words. We attach extra letters known as affixes to modify its meaning. We put the prefix before the root word. We attach a suffix at the end of the root word. Here are some common prefixes and their meanings: PREFIX MEANING EXAMPLES re- again; do for another time re try – to try again re read – to read again re play- to play again un- not; opposite of un clean – not clean un pleasant – opposite of pleasant un breakable – not breakable dis- no or not (it is usually used for adjectives) dis honest – not honest dis