Double that consonant?

I ran across this word in a piece of copy the other day: weasely (that is, in the manner of a weasel). I looked the word up because I thought it should be spelled “weaselly” (weasel + ly). I was right. Later, I had to look up the past tense of the verb “benefit” for what seems like the thousandth time (I have a mental block on this word). The spelling is “benefited,” (not “benefitted”). These two words led me to think about spelling rules.

Here are some rules about adding suffixes to words that end in consonants.

* If a one-syllable word ends in a single consonant preceded by a single vowel, double the final consonant before a suffix beginning with a vowel or before the suffix y.

Examples: bag – bagged, run – running, stop – stopped, fog – foggy.

Some exceptions: yes – yeses, gas – gases, sew – sewing, box – boxy.

* If a multiple-syllable word ends in a single consonant preceded by a single vowel and the accent is on the last syllable of the root word, double the final consonant before a suffix beginning with a vowel.

Examples: refer – referred, occur – occurrence, control – controlled.

Exceptions: obey – obeyed.

But if the accent shifts from the second syllable when the suffix is added, don’t double the consonant.

Example: refer – reference.

* If a one-syllable word ends in a single consonant preceded by a single vowel, do not double the final consonant before a suffix beginning with a consonant.

Examples: bad – badly, play – playful.

* If a multiple-syllable word ends in a single consonant preceded by a single vowel and the accent does not fall on the last syllable of the root word, do not double the final consonant before a suffix beginning with a vowel.

Examples: benefit – benefited, cancel – canceled, differ – different.

Some exceptions: program – programming, outfit – outfitting, kidnap – kidnapped.

* If a multiple-syllable word ends in a single consonant preceded by more than one vowel, do not double the final consonant before any suffix. (CORRECTION PROMPTED BY COMMENT 1: This rule should begin: If a ONE-SYLLABLE or a multiple-syllable word … )

Examples: dream – dreamy, chief – chiefly, equal – equaled.

Exceptions: quiz – quizzed, quizzing, equip – equipping.

* If a word ends with more than one consonant, do not double the final consonant before any suffix.

Examples: comb – combing, return – returned, harp – harping.

But if you add -ly to a word that ends in double l, drop one of the l’s: full – fully. (Just remember that you won’t have three l’s in a row.)

This article was originally posted by the Raleigh News & Observer, a subsidiary of The McClatchy Co.; is posted here to provide continuity; and is copyright © 2011 The News & Observer Publishing Company, which reserves the right to remove this post.