What You'll Find in This Free Guide:

What Is a Prefix?

The Two Most Common Prefixes

The most common prefixes are un and re.

         

These two prefixes are the most useful for beginning spellers to learn because they appear frequently and their meanings are easy to understand.

Un means not (unhappy = not happy) or the reverse of or opposite of (untie).

Re means again (redo = do again) or back (repay).                 

Handy Tips for Adding Prefixes

• The spelling of the base word never changes. Simply add the prefix to the beginning of the base word, as in the word unhappy.

• The spelling of the prefix never changes. A prefix will be spelled the same no matter what base word it is attached to. For example, if you learn to spell the prefix poly, as in polygon, you can depend on poly to be spelled the same in the words polygraph, polyester, and polygram.

• Be aware that double letters can occur. If you add the prefix un to natural, both the prefix and the base word retain their original spelling. The result is unnatural. Take a look at these other words where double letters occur:
  
  il + logical = illogical
  im + mature = immature
  il + legal = illegal
  un + necessary = unnecessary
  
  Other examples: unnoticeable, illiteracy, immaterial, immeasurable, immigrant, immobile, immoral, dissatisfy, disservice, dissimilar, dissolve, irreconcilable, irredeemable, irreducible, irregular, irrelevant, irreparable, irrestistible, irresponsible, misspoke, misspell, misstep

• Watch out for prefix look-alikes. Some words contain the same string of letters as a prefix, but upon closer examination you’ll find that they are not prefixes. The re in real is not a prefix. Other examples include uncle, pretty, press, interest, reach, irony, dish, and antique.
  

Six Rules for Using Hyphens with Prefixes

1. Hyphenate when the prefix comes before a proper noun or a numeral.
   
   Examples: un-American, pre-1980
   
   
2. Hyphenate when adding the prefix ex meaning former.
   
   Example: ex-president
   (Do not use a hyphen if ex means out of or away from, as in expel.)
   
   
3. Hyphenate after the prefix self.
   
   Examples: self-respect, self-assured, self-control
   
   
4. Hyphenate to separate two a’s, two i’s, or other letter combinations that might cause misreading or mispronunciation.
   
   Examples: ultra-ambitious, anti-intellectual, co-worker
   
   
5. A hyphen may be used to separate two e’s or two o’s to improve readability or prevent mispronunciation.
   
   Examples:
   co-opt and co-owner vs. coordinate
   de-emphasize vs. reenter
   
   (Note that many words with double e’s used to be hyphenated as a general rule, as in re-elect, re-establish, and pre-existing. However, current style manuals and dictionaries now tend toward “closing” the word except in cases where readability is affected. Both versions are currently accepted and listed in most dictionaries.)
   
   
6. A hyphen is sometimes used after the prefix re to prevent misreading or confusion with another word.
   
   Examples:
   re-cover vs. recover, as in Re-cover the boat when you recover from the flu.
   re-lay vs. relay, as in Please relay the message that they will re-lay the tiles.

Activities for Learning Prefixes

1. Practice adding prefixes to base words to form new words. Start with a common prefix such as re and have students add the prefix to simple base words. Words for this activity can be written on index cards or slips of paper. Be sure to discuss the meanings of the new words. Once students are comfortable with the activity, they can practice combining other prefixes and words.
   
   re  +     do     =    redo
   re +    build    =    rebuild
   re +     open     =    reopen
   re +    think    =    rethink
   re +    fill    =    refill
   re +    pay    =    repay
   re +    make    =    remake
   re +    move    =    remove
   re +    place    =    replace
   re +    turn    =    return
   
   
2. Create a Prefix List. Start with a few examples and have students add to the list as they discover words with prefixes. Discuss the meanings of the words on the list as they are added.
   
   
3. Look up prefixes in the dictionary and examine the entries near the word. When students look up the word hydro, for example, they’ll find hydroelectric, hydropower, and hydrophobia. Discuss how the prefix affects the meaning of the base word.
   

Resource List of 90 Prefixes