Doubling Final Consonants Study Guide

based on 27 ratings
Updated on Sep 28, 2011

Doubling Final Consonants

This lesson will cover the last of the special situations where a word must undergo changes before an ending can be added to it.

AS YOU ARE no doubt beginning to realize, there are many rules that govern the changes that words require when suffixes are added to them. There are rules that tell you which types of suffixes can be added to which types of words. Then there are rules about words that end in y and e. Now, we'll learn about words that require you to double their final consonants when adding an ending.

At first glance, you may see no logical reason why final consonants are sometimes doubled and sometimes not. But in fact, there are three simple yet key rules that govern the doubling of consonants before a suffix. When adding a suffix to a word that ends in a consonant, you double that consonant if

  • the ending begins with a vowel: run + ing = running, log + ed = logged
  • the last syllable of the word is accented and that syllable ends in a single consonant preceded by a single vowel: begin + ing = beginning (words of only one syllable are accented by definition and therefore follow the same rule: stop + er = stopper)

TIP: Many people have trouble with the word occur. But you can master its spelling by remembering the consonant-doubling rules you have just learned. Occur becomes occurring, occurred, and occurrence. The final consonant in occur is doubled because the last syllable in the word is accented and that syllable ends in a single consonant preceded by a single vowel. The word occur already contains a double consonant pair— cc—so people may be reluctant to double the final r. Don't be afraid to have two sets of double consonants in a word if it fits the requirements or doubling the final consonant.

Here are some examples of words that meet the doubling requirements for final consonants when you add an ending that begins with a vowel.

  • run = running, runner, runny
  • slam = slammed, slamming, slammer
  • nag = nagged, nagging
  • incur = incurred, incurring
  • kid = kidded, kidding, kidder
  • plan = planned, planning, planner
  • begin = beginning, beginner
  • set = setting, setter
  • transmit = transmitted, transmitting, transmittal
  • beg = begged, begging, beggar
  • submit = submitted, submitting, submittal, submitter
  • grin = grinned, grinning, grinner

When adding a suffix that begins with a vowel to a word that ends in a consonant, you do not double that consonant if

  • the accent is on the first syllable: cover + ed= covered
  • the final consonant is preceded by another consonant rather than by a single vowel: part + ing =parting
  • the final consonant is preceded by more than one vowel: sleep + er = sleeper

TIP: There are a few exceptions to the rules for doubling final consonants. Some words that seem to fit the requirements actually don't double the final consonant. Two exceptions are

    bus + es = buses and chagrin + ed = chagrined

In addition, most words that end in -w or -x do not double their final consonant:

  • draw = drawer, drawing
  • few = fewer
  • show = showing, shower, showed
  • glow = glowed, glowing, glower
  • tax = taxed, taxing, taxable
  • wax = waxed, waxing

Practice exercises for this study guide can be found at:

Doubling Final Consonants Practice Exercises

Add your own comment